20251014Compliance Filing.pdf

I ,1
October 14, 2025
IDAHO PUBLIC
Avista Corp. UTILITIES COMMISSION
1411 East Mission P.O. Box 3727
Spokane, Washington 99220-0500
Telephone [phone]
Toll Free 800-727-9170
October 14, 2025
Monica Barrios-Sanchez
Commission Secretary
Idaho Public Utilities Commission
11331 W. Chinden Blvd. Bldg. 8 Suite 201-A
Boise, Idaho 83714
Dear Commission Secretary,
Purchase Cost Adjustment (PCA) Report for the Quarter Ended September 2025
Pursuant to Order No. 36339, enclosed is an electronic copy of Avista's electric Power Cost
Adjustment(PCA) report for quarter ended September 30, 2025.
As identified within the Order, the Company is including two additional files:
1. Attachment A—Q3 2025 -Power Transaction Register("PTR")
2. Attachment B—Q3 2025 - Gas Accounting Data Download("GADD")
The provided attachments contain TRADE SECRET, PROPRIETARY or CONFIDENTIAL
information and are filed under IDAPA 31.01.01, Rule 067 and 233, and Section 9-340D, Idaho
Code.
For the quarter ended September 30,2025,total power supply expenses were lower than authorized
for the Idaho jurisdiction by $2,661,6811 as shown on page 43 (line 322) of the attached report.
For the July 2025 through June 2026 PCA reporting period,including the impact of the EIM O&M
deferral, WA I-937 renewable energy credit benefits, and interest the total deferral is currently a
rebate of$278,151 (page 40).
If you have any questions,please contact Ryan Finesilver at(509) 495-4873.
'Excluding adjustments related to EIM expenses.
2 Total of July,August,and September values on line 35.

Sincerely,
IS/Patrick D. Eli -bcw
Patrick D. Ehrbar
Director of Regulatory Affairs

Q3 2025 ID PCA Quarterly Report
AVISTA UTILITIES
POWER COST ADJUSTMENT REPORT
THIRD QUARTER 2025
MONTH OF JULY
Page 1

Q3 2025 ID PCA Quarterly Report
Avista Corporation Journal Entry Printed 08/06/2025 at 3:18 PM
Journal: 480-ID PCA Effective Date: 202507
Team: Resource Accounting Last Saved by: Jennifer Hossack Last Update:08/06/2025 3:16 PM
Type: C Submitted by: Jennifer Hossack Approval Requested:08/06/2025 3:17 PM
Category: DJ Approved by:
Currency: USD
Seq. Co. FERC Ser. Jur. S.I. Debit Credit Comment
5 001 557380-IDAHO PCA-DEF ED ID DL 0.00 1,132,826.00 kurrent Deferral Expense-PCA
10 001 182386-REGULATORY ASSET ID PCA ED ID DL 1,132,826.00 0.00 Current Deferral Reg Asset-PCA
DEFERRAL 2
20 001 182385-REGULATORY ASSET ID PCA ED ID DL 0.00 32,975.00 vPending Deferral-PCA
DEFERRAL 1
30 001 431600-INTEREST EXPENSE ENERGY ED ID DL 32,975.00 0.00 Interest Exp on Pending 182385
DEFERRALS
60 001 182387-REGULATORY ASSET ID PCA ED ID DL 631,802.00y, 0.00 Amortizing Deferral 182387
DEFERRAL 3
70 001 557390-IDAHO PCA AMT ED ID DL 0.00 631,802.00 vAmortizing Deferral 182387
80 001 182387-REGULATORY ASSET ID PCA ED ID DL 0.00 14,119.00-/Amortizing Deferral Interest Expense 182387
DEFERRAL 3
90 001 431600-INTEREST EXPENSE ENERGY ED ID DL 14,119.00 0.00 Amortizing Deferral Interest Expense
DEFERRALS
Totals: 1,811,722.00 1,811,722.00
Explanation: 64-� 08/06/25
Prepared by Jennifer Hossack Date
Record deferral of power costs in Idaho,amortization of existing balance,and � fo�f 8/6/25
Ainterest&DFIT entries.
Reviewed by Date
Approved for Entry Date
Corporate Accounting use Only
Page 1 of 1
Page 2

Q3 2025 ID PCA Quarterly Report
Idaho Power Cost Adjustment(PCA)Deferral Balance-Current Year Bucket
Interest compounds and is calculated monthly
Interest Rate
2024 0.41667%
2025 0.416679/6
Balance Deferral- Interest
Month Ending Account Be .Balance Transfer Surd Reb. Ad'ustments Interest Ad'ustments Balance with Interest GLW Balance Recon Adjustment Notes
12/31/2024 182385 (7,714,835)
1/31/2025 182385 7,714,835 1,447,025 28,985 32,145 9,165,020 9,165,020 DJ240 EIM Deferral
2/28/2025 182385 9,165,020 1,165,452 23,785 38,188 8,013,971 8,013,971 DJ240 EIM Deferral
3/31/2025 182385 8,013,971 197,621 22,795 33,392 8,222,189 8,222,189 DJ240 EIM Deferral
4/30/2025 182385 8,222,189 1,072,522 28,878 34,259 9,300,092 9,300,091 1 DJ240 EIM Deferral
5/31/2025 182385 9,300,092 204,530 26,665 38,751 9,516,707 9,516,707 DJ240 EIM Deferral
6/30/2025 182385 (9 07) 1,606,715 35,666 (39,653) (7,913,979) (7,913,979) G �/ DJ240 EIM Deferral
This account moves to the Pendin tab
6/30/2025 182386 This account moves from the Pending tab
7/31/2025 182386 a-ol 1,132,826 2,956,729 C 0 1,823,903 2,956,729 1,132,826 WA 1-937&CETA Compliance&EIM Deferral
8/31/2025 182386
9/30/2025 182386
10/31/2025 182386
11/30/2025 182386
12/31/2025 182386
1,132,826 -
Entry:
Debit Credit
557380 ED ID 1,132,826 vfdaho PCA-Def
182386 ED ID 1,132,826 V Regulatory Asset ID PCA Deferral
Adj us t nent
VIA I937 CETA (�2,987,874.44 -
EIM 031,145.70 +
Total - 2 items -2,956,728.74 T
C
Page 3
H:\Power Deferrals\Power Deferral Joumals\2 ID PCA\2025 ID PCA\2025 DJ480 ID PCA.xlsx

Q3 2025 ID PCA Quarterly Report
Idaho Power Cost Adjustment(PCA)Deferral Balance-Pending Bucket
Interest compounds and is calculated monthly
Interest Rate
2024 0.41667%
2025 0.41667
Balance Interest Balance with
Month Ending Account iB&Bili&Transfer Activity Adjustments Interest Adjustments Interest GLW Balance Recon Adjustment Notes
12/31/2024 182386 -
1/31/2025 182386
2/28/2025 182386
3/31/2025 182386
4/30/2025 182386
5/31/2025 182386
6/30/20251 182386
This account moves to the Current Year tab
6/30/2025 182385 This account moves from the Current Year tab G (7,913,979)
7/31/2025 182385 7,913,979 32,975 7,946,954 7,913,979 32,975
8/31/2025 182385
9/30/2025 182385
10/31/2025 182385
This account moves to the Amortizingtab
10/31/20251 182387 This account moves from the Amortizing tab
11/30/20251 182387
12/31/2025 182387
(32,975)
Entry:
Debit Credit
431600 ED ID 32,975 Interest Exp Energy Deferrals
182385 ED ID 32,975AegulatoryAsset ID PCA Deferral
Page 4
H:\Power Deferrals\Power Deferral Journals\2 ID PCA\2025 ID PCA\2025 DJ480 ID PCA.xlsx

Q3 2025 ID PCA Quarterly Report
Idaho Power Cost Adjustment(PCA)Deferral Balance-Amortizing Bucket
Interest compounds and is calculated monthly
Interest Rate
?2?11
0.,E6:7
2025 0.41667%
Balance Interest Balance with
Month Ending Account Be .Balance Transfer Amortization Adjustments Interest Adjustments Interest GLW Balance Recon Adjustment Notes
12/31/2024 182387 (7,197,201:
1/31/2025 182387 7,197,201 766,605 29,988.58 6,460,585 6,460,585
2/28/2025 182387 6,460,585 757,753 26,919.32 5,729,751 5,729,751
3/31/2025 182387 5,729,751 671,679 23,874.15 5,081,946 5,081,946
4/30/2025 182387 5,081,946 625,760 21,174.94 4,477,361 4,477,361
5/31/2025 182387 4,477,361 542,748 18,655.82 3,953,269 3,953,269
6/30/2025 182387 3,953,269 581,283 16,472.09 3,388,458 3,388,458
7/31/2025 182387 3,388,458 V Ii-02 631,802 14,119 2,770,775 3,388,458 617,683
8/31/2025 182387
9/30/2025 182387
10/31/2025 182387
This account moves to the Pending tab
10/31/20251 182385 This account moves from the Pending tab
11/30/20251 182385 0
12/31/20251 182385
631,802 (14,119)
Entry:
Debit Credit
182387 ED ID 631,802 d Regulatory Asset ID PCA Deferral
557390 ED ID 631,802 vfdaho PCA Amt
431600 ED ID 14,119 Interest Expense Energy Deferrals
182387 ED ID 14,119 1IRe ulato Asset ID PCA Deferral
Page 5
H:\Power Deferrals\Power Deferral Journals\2 ID PCA\2025 ID PCA\2025 DJ480 ID PCA.xlsx

Q3 2025 ID PICA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO POWER COST DEFERRALS
Line
No. IDAHO ACTUALS TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25
1 555 Purchased Power $123,683,036 $14,649,944 $22,918,792 $17,154,312 $15,506,870 $16,498,614 $17,744,546 $19,209,958 $0 $0 $0 $0 $0
2 447 Sale for Resale ($117,288,748) ($15,815,928) ($17,283,171) ($18,540,183) ($16,913,483) ($14,491,131) ($16,307,443) ($17,937,409) $0 $0 $0 $0 $0
3 501 Thermal Fuel $22,129,251 $3,455,873 $4,522,795 $3,752,557 $1,697,225 $1,525,413 $2,568,207 $4,607,181 $0 $0 $0 $0 $0
4 547 CT Fuel $62,439,735 $13,795,379 $12,944,613 $10,184,136 $5,401,423 $3,985,276 $8,335,950 $7,792,958 $0 $0 $0 $0 $0
5 456 Transmission Rev ($19,180,112) ($2,968,699) ($2,980,575) ($2,877,392) ($2,606,548) ($2,690,461) ($2,446,343) ($2,610,094) $0 $0 $0 $0 $0
6 565 Transmission Exp $16,920,310 $2,251,109 $2,251,996 $2,656,824 $2,476,343 $2,399,160 $2,395,608 $2,489,270 $0 $0 $0 $0 $0
7 537 MT Invasive Species Exp $453,054 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $0 $0 $0 $0 $0
8 557 Expenses $201,540 $7,057 $8,599 $53,596 $57,166 $69,241 $3,779 $2,102 $0 $0 $0 $0 $0
9 Adjusted Actual Net Expense $89,358,066 $15,439,457 $22,447,771 $12,448,572 $5,683,718 $7,360,834 $12,359,026 $13,618,688 $0 $0 $0 $0 $0
AUTHORIZED NET EXPENSE-SYSTEM YTD Jan/25 Feb/25 Mar/25 Apr/25 May/25 Jun/25 Jul/25 Aug/25 Sep/25 Oct/25 Nov/25 Dec/25
10 555 Purchased Power $ 44,548,500 7,435,932 7,069,211 7,433,801 5,672,869 5,579,483 5,419,545 5,937,659 5,836,088 5,942,565 6,184,512 6,489,810 6,556,792.00
11 447 Sale for Resale $ (29,934,570) (2,316,991) (1,936,564) (2,540,468) (4,230,873) (3,489,856) (5,862,698) (9,557,120) (4,493,194) (7,072,562) (3,997,529) (2,672,014) (4,453,080.00)
12 501 Thermal Fuel $ 17,046,320 3,151,777 2,749,966 2,896,333 2,060,445 1,526,412 1,782,225 2,879,162 3,146,005 3,033,757 2,874,156 2,395,831 3,087,726.00
13 547 CT Fuel $ 37,676,945 8,942,104 7,474,530 5,068,911 4,095,763 2,284,385 3,117,887 6,693,265 7,977,571 8,729,385 8,223,214 8,133,493 10,790,239.00
14 456 Transmission Revenue $ (13,751,745) (1,634,727) (1,811,669) (1,891,560) (1,715,927) (2,123,305) (2,306,697) (2,267,860) (2,209,469) (1,714,509) (1,711,129) (1,937,530) (2,146,621.00)
15 565 Transmission Expense $ 10,079,279 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897.00
16 90%Palouse Wind and Rattlesnake Flats $ 17,099,250 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750.00
17 Remove Columbia Basin Hydro Transmission Project$ (587,419) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917.00)
18 Gas Liquids Revenue/Acct 456 Other Rev Sep-Dec $ (4,360,233) (633,351) (664,038) (880,329) (385,474) (657,028) (615,703) (524,310) (514,471) (290,007) (311,801) (548,421) (265,977.00)
19 Montana Invasive Species Expense $ 939,169 134,167 134,167 134,167 134,167 134,167 134,167 134,167 134,167 134,167 134,167 134,167 134,167.00
20 Settlement Adjustments/Other Exp 557 Sep-Dec $ 368,452 52,636 52,636 52,636 52,636 52,636 52,636 52,636 52,636 52,636 52,636 52,636 52,636.00
21 Authorized Net Expense $79,123,848 18,930,277 16,866,969 14,072,221 9,482,336 7,105,624 5,520,092 7,146,329 13,728,063 12,614,162 15,246,956 15,846,702 17,554,612.00
22 Actual-Authorized Net Expense $10,234,218 ($3,490,820) $5,580,802 ($1,623,649) ($3,798,618) $255,210 $6,838,934 $6,472,359 1I
23 Resource Optimization ($770,139) $209,703 ($101,488) $502,625 ($359,215) ($146,870) ($41,017) ($833,877) t/ $0 $0 $0 $0 $0
24 Adjusted Actual-Authorized Net Expense $9,464,079 ($3,281,117) $5,479,314 ($1,121,024) ($4,157,833) $108,340 $6,797,917 $5,638,482
25 Idaho Allocation 34.47% 34.47% 34.47% 34.47% 34.47% 34.47% 34.47% 34.47% 34.47% 34.47% 34.47% 34.47%
26 Idaho Share $3,262,269 ($1,131,001) $1,888,720 ($386,417) ($1,433,205) $37,345 $2,343,242 $1,943,585
27 Idaho 100%Activity(Clearwater) ($557,201) ($70,325) ($91,841) ($73,997) ($72,895) ($85,016) ($81,355) ($81,772) $0 $0 $0 $0 $0
ID Load Change Adjustment(+)Surcharge;(-) ($1,612,518) ($406,480) ($501,932) $240,835 $314,409 ($179,585) ($476,648) R-03($603,117)Vf
28 Rebate
29 Net Power Cost Increase(+)Surcharge;(-) $1,092,550
Rebate ($1,607,806) $1,294,947 ($219,579) ($1,191,691) ($227,256) $1,785,239 $1,258,6961I
30 90%of Net Power Cost Change $983,295 ($1,447,025) $1,165,452 ($197,621) ($1,072,522) ($204,530) $1,606,715 $1,132,826
R-01
31 Acct 557380 Entry;(+)Rebate,(-)Surcharge ($983,295) $1,447,025 ($1,165,452) $197,621 $1,072,522 $204,530 ($1,606,715) ($1,132,826)
32 Energy Imbalance Market Incremental O&M Costs $219,911 $32,205 $26,428 $25,328 $32,087 $29,628 $39,629 $34,606 $0 $0 $0 $0 $0
33 90%of Energy Imbalance Market $197,919 $28,985 $23,785 $22,795 $28,878 $26,665 $35,666 $31,145 $0 $0 $0 $0 $0
34 Acct 407434 Entry;(+)Rebate,(-)Surcharge ($197,919) ($28,985) ($23,785) ($22,795) ($28,878) ($26,665) ($35,666) ($31,145) $0 $0 $0 $0 $0
35 Total Deferral Balance Sheet Entry ($1,181,214) ($1,418,040) $1,189,237 ($174,826) ($1,043,644) ($177,865) $1,642,381 $1,163,971 $0 $0 $0 $0 $0
Page,A.1 of 4
2025 WA ID Actual Deferrals.xlsx-8/6/2025

Q3 2025 ID PICA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO DEFERRED POWER COST CALCULATION-ACTUAL SYSTEM POWER SUPPLY EXPENSES
Line
No. TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 00-25 Nov-25 Dec-25
555 PURCHASED POWER
1 Other Short-Term Purchases $19,854,376 $2,347,807 $9,949,684 $1,726,673 ($17,697) $543,667 $2,077,148 $3,227,094 $0 $0 $0 $0 $0
2 Chelan County PUD(not in settlement) $9,758,567 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $0 $0 $0 $0 $0
3 Chelan County PUD(in settlement) $12,534,536 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $0 $0 $0 $0 $0
4 Douglas County PUD(Wells Settlement) $370,117 $37,007 $27,060 $36,071 $51,732 $55,201 $51,782 $111,264 $0 $0 $0 $0 $0
5 Douglas County PUD(Wells) $660,723 $94,389 $94,389 $94,389 $94,389 $94,389 $94,389 $94,389 $0 $0 $0 $0 $0
6 Grant County PUD(Priest Rapids/Wanapum) $19,736,554 $2,817,090 $2,817,090 $2,817,090 $2,834,014 $2,817,090 $2,817,090 $2,817,090 $0 $0 $0 $0 $0
7 Bonneville Power Admin.(WNP-3)' 573-Enter $0
8 Inland Power&Light-Dear Lake $6,116 $929 $1,062 $1,156 $767 $740 $776 $686 $0 $0 $0 $0 $0
9 Small Power $738,985 $91,551 $67,808 $128,480 $143,116 $121,014 $104,932 $82,084 $0 $0 $0 $0 $0
10 Clearwater Wind III,LLC $6,851,216 $1,327,691 $986,871 $1,071,271 $901,880 $1,055,322 $773,983 $734,198 $0 $0 $0 $0 $0
11 City of Spokane-Upriver $1,684,265 $322,436 $129,608 $422,448 $356,808 $358,390 $94,575 $0 $0 $0 $0 $0 $0
12 City of Spokane-Waste-to-Energy $3,767,388 $684,124 $619,347 $518,361 $477,857 $335,476 $500,920 $631,303 $0 $0 $0 $0 $0
13 East,South,Quincy Columbia Basin Irrigation Dist $12,165,263 $0 $0 $484,065 $2,269,922 $3,061,573 $3,077,978 $3,271,725 $0 $0 $0 $0 $0
14 Rathdrum Power,LLC(Lancaster PPA) $15,802,308 $2,164,734 $2,373,653 $2,327,189 $2,085,304 $1,964,612 $2,457,245 $2,429,571 $0 $0 $0 $0 $0
15 Palouse Wind $11,843,960 $969,296 $1,601,821 $2,697,346 $1,914,119 $1,684,273 $1,459,184 $1,517,921 $0 $0 $0 $0 $0
16 Rattlesnake Flat,LLC $6,571,747 $390,336 $753,072 $1,485,098 $1,140,611 $1,038,716 $904,696 $859,218 $0 $0 $0 $0 $0
17 WPM Ancillary Services $771,658 $111,115 $194,678 $88,561 $87,492 $83,461 $99,714 $106,637 $0 $0 $0 $0 $0
18 Non-Mon.Accruals $565,257 $106,710 $117,920 $71,385 ($18,173) $99,961 $45,405 $142,049 $0 $0 $0 $0 $0
19 Total 555 Purchased Power $123,683,036 $14,649,944 $22,918,792 $17,154,312 $15,506,870 $16,498,614 $17,744,546 $19,209,958 $0 $0 $0 $0 $0
555 PURCHASED POWER
555000 $124,006,060 $13,866,745 $21,620,393 $17,220,716 $17,484,550 $17,494,009 $17,252,770 $19,066,877 $0 $0 $0 $0 $0
555030 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555200 ($100,880) $0 $0 $0 ($100,880) $0 $0 $0 $0 $0 $0 $0 $0
555312 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555313 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555380 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555550 $565,257 $106,710 $117,920 $71,385 ($18,173) $99,961 $45,405 $142,049 $0 $0 $0 $0 $0
555700 $2,687,158 $39,120 $572,008 $585,151 $208,432 $85,450 $1,111,797 $85,200 $0 $0 $0 $0 $0
20 Solar Select Adjustment ($64,134) ($5,418) ($5,500) ($8,078) ($10,881) ($10,919) ($11,858) ($11,480)✓ $0 $0 $0 $0 $0
21 555380 $10,381,297✓ $1,512,232 $1370915 $1,499,825 $1,536,936 $1,516,066 $1,444,087 $1,501,236✓ $0 $0 $0 $0 $0
22 Clearwater Adjustment ($10,381,297)✓ ($1,512,232) ($1:370:915) ($1,499,825) ($1,536,936) ($1,516,066) ($1,444,087) ($1,501,236)✓ $0 $0 $0 $0 $0
23 Chelan Adj of LMC vs Contract Price ($3,052,755) $ (3,686) $ (87,076) $ (991,655) $ (814,080) $ (324,448) $ (377,821) $ (453,989 R OS _ $ $ _ $ $ _
24 Columbia Basin Adj of LMC vs Contract Price ($2,866,207) $ - $ - $ (532,293) $ (1,134,597) $ (681,394) $ (517,923) $ - R-04 $ $ $ $
25 Company Absorbed Wind Adjustment ($1,841,570) ($135,963) ($235,489) ($418,244) ($305,473) ($272,299) ($236,388) ($237,714 $0 $0 $0 $0 $0
555710 $771,658 $111,115 $194,678 $88,561 $87,492 $83,461 $99,714 $106,637 $0 $0 $0 $0 $0
555740 $3,578,449 $671,321 $741,858 $1,138,769 $110,480 $24,793 $378,850 $512,378 $0 $0 $0 $0 $0
$123,683,036 $14,649,944 $22,918,792 $17,154,312 $15.506.870 $16,498,614 $17,744,546 $19,209,958 $0 $0 $0 $0 $0
($682,037)
447 SALES FOR RESALE
26 Short-Term Sales ($86,225,433) ($12,168,965) ($13,083,760) ($14,197,853) ($11,728,570) ($9,705,613) ($11,217,958) ($14,122,714) $0 $0 $0 $0 $0
27 Nichols Pumping Index Sale ($855,831) ($132,824) ($151,283) ($82,969) ($63,712) ($93,333) ($123,074) ($208,636) $0 $0 $0 $0 $0
28 Soverign/Kaiser Load Following $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
29 Pend Oreille DES ($311,533) ($47,098) ($41,677) ($43,507) ($43,870) ($45,562) ($41,049) ($48,770) $0 $0 $0 $0 $0
30 Merchant Ancillary Services ($29,895,951) ($3,467,041) ($4,006,451) ($4,215,854) ($5,077,331) ($4,646,623) ($4,925,362) ($3,557,289) $0 $0 $0 $0 $0
31 Total 447 Sales for Resale ($117,288,748) ($15,815,928) ($17,283,171) ($18,540,183) ($16,913,483) ($14.491,131) ($16,307,443) ($17,937,409) $0 $0 $0 $0 $0
447 SALES FOR RESALE
447000 ($61,299,314) ($8,D42,952) ($10,073,662) ($8,948,674) ($7,610,973) ($8,776,385) ($11,110,798) ($6,735,870) $0 $0 $0 $0 $0
32 Deduct Revenue From Solar Select $962,506 $64,839 $65,458 $74,296 $106,010 $171,239 $224,635 $256,029,/ $0 $0 $0 $0 $0
447100 ($2,520,757) ($620,226) $1,031,D40 ($2,100,093) ($1,681,328) $1,339,548 $3,629,520 ($4,119,218) $0 $0 $0 $0 $0
447150 ($15,734,354) ($2,829,559) ($3,357,951) ($1,727,094) ($1,353,212) ($1,884,091) ($2,038,731) ($2,543,716) $0 $0 $0 $0 $0
447700 ($3,457,516) ($42,410) ($618,313) ($1,075,555) ($458,793) ($56,009) ($1,115,014) ($91,422) $0 $0 $0 $0 $0
447710 ($771,658) ($111,115) ($194,678) ($88,561) ($87,492) ($83,461) ($99a14) ($106,637) $0 $0 $0 $0 $0
447720 ($29,895,951) ($3,467,041) ($4,006,451) ($4,215,854) ($5,077,331) ($4,646,623) ($4,925,362) ($3,557,289) $0 $0 $0 $0 $0
447740 ($4,571,704) ($767,464) ($128,614) ($458,648) ($750,364) ($555,349) ($871,979) ($1,039,286) $0 $0 $0 $0 $0
($117,288,748) ($15,815,928) ($17,283,171) ($18,540,183) ($16,913,483) ($14,491,131) ($16,307,443) ($17,937,409) $0 $0 $0 $0 $0
501 FUEL-DOLLARS
33 Kettle Falls Wood-501110 $4,217,804 $933,844 $797,711 $883,284 ($5,108) $0 $678,159 $929,914 $0 $0 $0 $0 $0
34 Kettle Falls Gas-501120 ($3,789) $287 $1,741 ($962) ($5,401) ($243) $1,539 ($750) $0 $0 $0 $0 $0
35 Colstrip Coal-501140 $17,741,423 $2,521,742 $3,676,147 $2,849,365 $1,696,656 $1,519,144 $1,866,322 $3,612,047 $0 $0 $0 $0 $0
36 Colstrip 011-501160 $173,813 $0 $47,196 $20,870 $11,078 $6,512 $22,187 $65,970 $0 $0 $0 $0 $0
37 Total 501 Fuel Expense $22,129,251 $3.455.873 $4.522.795 $3.752.557 $1.697.225 $1.525.413 $2.568.207 $4,607,181 $0 $0 $0 $0 $0
501 FUEL-TONS
38 Kettle Falls 218,517 47,598 41,680 46,433 - - 35,047 47,759 - - - - -
39 Colstrip 485,584 90,120 82,086 78,070 46,696 40,389 51,303 96,920 - - - - -
501 FUEL-COST PER TON
40 Kettle Falls wood $19.62 $19.14 $19.02 $19.35 $19.47
41 Colstrip coal $27.98 $44.78 $36.50 $36.33 $37.61 $36.38 $37.27
Page 7
2025 WA ID Actual Deferrals.xlsx ID Monthly 2

Q3 2025 ID PICA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO DEFERRED POWER COST CALCULATION-ACTUAL SYSTEM POWER SUPPLY EXPENSES
Line
No. TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25
547 FUEL
42 NE CT Gas-547213 ($5,173) $1,211 $639 ($1,163) ($5,082) ($324) $453 ($907) $0 $0 $0 $0 $0
43 Boulder Park-547216 $1,553,809 $90,977 $373,870 $266,081 $158,946 $108,083 $249,552 $306,300 $0 $0 $0 $0 $0
44 Kettle Falls CT-547211 $19,165 $3,074 $3,102 $1,817 $10,082 $454 ($636) $1,272 $0 $0 $0 $0 $0
45 Coyote Springs2-547610 $25,179,356 $5,503,409 $4,984,616 $4,197,442 $2,644,029 $1,925,515 $3,360,708 $2,563,637 $0 $0 $0 $0 $0
46 Lancaster-547312 $20,410,136 $4,823,423 $4,344,662 $3,664,728 $1,295,217 $689,411 $2,794,405 $2,798,290 $0 $0 $0 $0 $0
47 Rathdrum CT-547310 $15,282,442 $3,373,285 $3,237,724 $2,055,231 $1,298,231 $1,262,137 $1,931,468 $2,124,366 $0 $0 $0 $0 $0
48 Total 547 Fuel Expense $62,439,735 $13,795,379 $12,944,613 $10,194,136 $5,401,423 $3,985,276 $8,335,950 $7,792,958 $0 $0 $0 $0 $0
49 TOTAL NET EXPENSE $90,963,274 $16.085.268 $23.103,029 $12,550,822 $5.692.035 $7,518,172 $12,341,260 $13,672,688 $0 $0 $0 $0 $0
202501 202502 202503 202504 202505 j 202506 202507 202508 202509 202510 202511 j 202512
456 TRANSMISSION REVENUE
50 456100 ED AN ($15,667,989) ($2,462,659) ($2,391,307) ($2,394,241) ($2,129,966) ($2,217,910) ($1,957,539) ($2,114,367) $0 $0 $0 $0 $0
51 456120 ED AN-BPA Trans. ($539,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) $0 $0 $0 $0 $0
52 456020 ED AN-Sale of excess BPA Trans $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
53 456030 ED AN-Clearwater Trans ($1,056,335) ($154,335) ($154,000) ($154,000) ($148,500) ($148,500) ($148,500) ($148,500) $0 $0 $0 $0 $0
54 456130 ED AN-Ancillary Services Revenue ($771,658) ($111,115) ($194,678) ($88,561) ($87,492) ($83,461) ($99,714) ($106,637) $0 $0 $0 $0 $0
55 456017 ED AN-Low Voltage ($70,441) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) $0 $0 $0 $0 $0
56 456700 ED ID-Low Voltage ($36,631) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) $0 $0 $0 $0 $0
57 456705 ED AN-Low Voltage ($1,038,058) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) $0 $0 $0 $0 $0
58 Total 456 Transmission Revenue ($19,180,112) ($2,968,699) ($2,980,575) ($2,877,392) ($2,606,548) ($2,690,461) ($2,446,343) ($2,610,094) $0 $0 $0 $0 $0
565 TRANSMISSION EXPENSE
59 565000 ED AN $16,878,471 $2,245,132 $2,246,019 $2,650,847 $2,470,366 $2,393,183 $2,389,631 $2,483,293 $0 $0 $0 $0 $0
60 565710 ED AN $41,839 $5,977 $5,977 $5,977 $5,977 $5,977 $5,977 $5,977 $0 $0 $0 $0 $0
61 Total 565 Transmission Expense $16,920,310 $2,251,109 $2,251,996 $2,656,824 $2,476,343 $2,399,160 $2,395,608 $2,489,270 $0 $0 $0 $0 $0
557 Expense
62 557165 ED AN CAISO $166,459 $2,984 $4,818 $26,074 $57,166 $69,241 $4,074 $2,102 $0 $0 $0 $0 $0
63 557167 ED AN $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
64 557018 ED AN Merchandis $7,429 $4,073 $3,781 ($130) $0 $0 ($295) $0 $0 $0 $0 $0 $0
65 557020 ED AN-Tariff Cost $27,652 $0 $0 $27,652 $0 $0 $0 $0 $0 $0 $0 $0 $0
66 Total 557 ED AN Broker&Related Fees $201,540 $7,057 $8,599 $53,596 $57,166 $69,241 $3,779 $2,102 $0 $0 $0 $0 $0
537 Expense
67 537000 ED AN-MT Invasive Species $453,054 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722
68 Total 537 ED AN MT Invasive Species $453,054 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $0 $0 $0 $0 $0
Other Purchases and Sales
69 Econ Dispatch-557010 $8,867,379 $1,480,819 $2,380,180 $3,023,389 $471,998 $333,049 $385,530 $792,414 $0 so $0 $0 $0
70 Econ Dispatch-557150 ($1,075,989) ($1,868,318) ($2,621,649) ($651,285) $1,671,560 $1,762,018 $462,563 $169,122 $0 $0 $0 $0 $0
71 Gas Bookouts-557700 $1,556,950 $468,775 $116,900 $309,405 $140,581 $0 $36,270 $485,019 $0 $0 $0 $0 $0
72 Gas Bookouts-557711 ($1,556,950) ($468,775) ($116,900) ($309,405) ($140,581) $0 ($36,270) ($485,019) $0 $0 $0 $0 $0
73 Intraco Thermal Gas-557730 $4,994,701 $1,155,447 $760,783 $1,030,660 $393,919 $143,763 $206,915 $1,303,214 $0 $0 $0 $0 $0
74 Fuel Dispatch456010 ($759,611) $224,169 ($56,875) ($357,856) ($469,275) ($99,774) $0 $0 $0 $0 $0 $0 $0
75 Fuel Dispatch456015 ($10,772,330) ($661,280) ($497,104) ($1,903,363) ($1,941,354) ($1,978,461) ($925,962) ($2,864,806) $0 $0 $0 $0 $0
76 Other Elec Rev-Extraction Plant Cr-456018 ($327,029) ($42,833) ($50,949) ($44,832) ($55,901) ($40,186) ($44,217) ($48,211) $0 $0 $0 $0 $0
77 Other Else Rev-Specified Source-456019 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
78 Intraco Thermal Gas-456730 ($1,741,466) ($77,453) ($16,045) ($638,673) ($430,223) ($267,373) ($125,954) ($185,745) $0 $0 $0 $0 $0
79 Fuel Bookouls-456711 $714,203 $61,063 $33,576 $172,721 $89,526 $3,817 $732 $352,768 $0 $0 $0 $0 $0
80 Fuel Bookouls-456720 ($714,203) ($61,063) ($33,576) ($172,721) ($89,526) ($3,817) ($732) ($352,768) $0 $0 $0 $0 $0
81 Other Purchases and Sales Subtotal ($814,345) $210,551 ($101,559) $458.040 ($359,276) ($146,964) ($41,125) ($834,012) $0 $0 $0 $0 $0
82 Misc Revs 456016 ED AN $43,635 ($900) $0 $44.535 $0 $0 $0 $0 $0 $0 $0 $0 $0
83 REC Revenue Subtotal $43,635 ($900) $0 $44,535 $0 $0 $0 $0 $0 $0 $0 $0 $0
84 Misc.Power Exp.Actual-557160 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
85 Misc.Power Exp.Subtotal $0 $0 $0 $0 $0 $0 $0 $0
86 Wind REC Exp Authorized $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
87 Wind REC Exp Actual 557395 $571 $52 $71 $50 $61 $94 $108 $135 $0 $0 $0 $0 $0
88 Wind REC Subtotal $571 $52 $71 $50 $61 $94 $108 $135
Page 8
2025 WA ID Actual Deferrals.tdsx ID Monthly 3

Q3 2025 ID PCA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO DEFERRED POWER COST CALCULATION-ACTUAL SYSTEM POWER SUPPLY EXPENSES
Line
No. TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25
89 456030 ED ID-Clearwater Trans $105,092 $14,308 $15,434 $15,400 $15,400 $14,850 $14,850 $14,850 $0 $0 $0 $0 $0
90 456380-ED-ID-Clearwater REC Revenue ($662,293) ($84,633) ($107,275) ($89,397) ($88,295) ($99,866) ($96,205) ($96,622) $0 $0 $0 $0 $0
91 Clearwater ($557,201) ($70,325) ($91,841) ($73,997) ($72,895) ($85,016) ($81,355) ($81,772) $0 $0 $0 $0 $0
92 Not Resource Optimlutlon ($770,139) $209,703 ($101,488) $502,625 ($359,215) ($146,870) ($41,017) ($833,877) $0 $0 $0 $0 $0
93 EIM Incremental O&M Costs(Idaho share) $219,911 $32205 $26428 $25328 $32087 $29628 $39629 B $34,606V
94 Adjusted Actual Net Expense $88,250,637 $15,611,040 $22,280,870 $12,902,528 $5,283,695 $7,158,576 $12,276,283 $12,737,645
OA 31,145.70 -
0.90 =
©34,606.33 T+
Page 9
2025 WA ID Actual Deferrals.xlsx ID Monthly 4

Q3 2025 ID PCA Quarterly Report
Avista Corp.-Resource Accounting
Idaho Electric Jurisdiction
Power Costs Adjustment (PCA) - Load Change Adjustment - 2025
Retail Revenue Credit excluding
Clearwater-MWh Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25 YTD
Total Billed Sales 312,860 309,308 274,035 255,324 221,646 237,222 257,843 V (41,505) 1,868,238
Deduct Prior Month Unbilled (137,264) (145,445) (132,541) (124,764) (106,829) (119,536) (127,614) (150,599) (893,993)
Add Current Month Unbilled 145,445 132,541 124,764 106,829 119,536 127,614 150,599 907,328
Total Retail Sales 321,041 296,404 266,258 237,389 234,353 245,300 280,828 (192,104) 1,881,573
Test Year Consumption 304,450 275,917 276,088 250,222 227,023 225,845 256,211 254,893 218,497 235,421 260,464 297,899 1,815,756
Difference from Test Year 16,591 20,487 (9,830) (12,833) 7,330 19,455 24,617 (446,997) 65,817
Load Change Adjustment Rate- $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50
$/M W h
Total Load Change Adjustment-$ $406,480 $501,932 ($240,835) ($314,409) $179,585 $476,648 R_03l $603,117vf ($10,951,427) $1,612,518
Page 10
Page 4 of 4

Q3 2025 ID PCA Quarterly Report
Electric Revenue Report by Revenue Class Data Source:Financial Reporting
Data Updated Daily
Accounting Period:202507 State Code:ID
Rate Schedule Desc Meter Qty Usage Qty Revenue Amt YTD Meter Qty YTD Usage I YTD Revenue Amt
0001-RESIDENTIAL 0 0 (252,597) 0 0 (1,978,985)
0011-GENERAL SERVICE 0 0 (190,039) 0 0 (1,295,517)
0012-RESID&FARM-GEN SERV 0 0 (6,244) 0 0 (58,199)
0021-LARGE GENERAL SERV 0 0 (17,089) 0 0 (151,790)
0022-RESID&FRM-LGE GEN SE 0 0 (1,355) 0 0 (10,609)
0025-EXTRA LGE GEN SERV 0 0 (68,861) 0 0 (507,143)
0031-PUMPING SERVICE 0 0 (22,221) 0 0 (84,846)
0032-PUMPING SVC RES&FRM 0 0 (2,765) 0 0 (8,072)
0042-CO OWND ST LTS SO VA 0 0 (1,053) 0 0 (7,375)
0044-CST OWND ST LT SO VA 0 0 (51) 0 0 (361)
0045-CUST OWND ST LT ENGY 0 0 (56) 0 0 (395)
0046-CUST OWND ST LT S V 0 0 (186) 0 0 (1,326)
0047-AREA LIGHT-COM&INDUS 0 0 (27) 0 0 (288)
0048-AREA LGHT-FARM&RESID 0 0 (147) 0 0 _ (1,070)
0049-AREA LGHT-HI PRIES SO 0 0 (413) 0 0 (2,877)
025 EXTRA LARGE GEN SERVICE/POTLATCH 0 0 (71,031) 0 0 (485,924)
10023-DCFC-ID 0 0 (61) 0 0 (208)
Overall-Summary 0 01 (60010m 0 0 i(4,594,985)
Page 1 of 3 Run Date:Aug 6,2025
IFor Internal Use Only
0.996223 Settlement Revenue Conversion Factor Changes October 1st w/GRC
R-021 (631802)
H:\Power Deferrals\Power Deferral Journals\2_ID PCA\2025 ID PCA\Cognos Reports\202507 Revenue_RateSch_CM_YTD for ID PCA.xlsx 84 025�2:38 PM

Q3 2025 ID PCA Quarterly Report
Revenue By Revenue Class Data Source: Financial Reporting
Electric Data Updated Daily
State Code:ID
Accounting Period Service I Revenue Class Revenue Class Desc Meter Qty Usage Qty Revenue Amt I YTD Average Meters YTD Usage YTD Revenue Amt
202507 �/ ED 01 01 RESIDENTIAL 129,103 106,232,938 12,401,284 128,791 834,849,915 95,582,877
21 21 FIRM COMMERCIAL 19,412 91,175,128 8,308,046 19,272 610,761,400 55,405,782
31 31 FIRM-INDUSTRIAL 317 98,732,831 4,977,358 317 698,104,352 35,361,614
39 39 FIRM-PUMPING-IRRIGATION ONLY 42 831,126 83,628 39 2,025,566 210,174
51 51 LIGHTING-PUBLIC STREET AND HIWAY 203 578,414 261,985 203 3,962,899 1,829,955
80 80 INTERDEPARTMENT REVENUE 53 217,454 20,875 54 1,548,381 141,448
83 83 MISC-SERVICE REVENUE SNP 0 0 8,820 0 0 65,404
85 85 MISC-RENT FROM ELECTRIC PROPERTY 0 0 9,548 0 0 66,833
OD OD Other Electric Direct 0 0 2,200 0 0 6,900
RP RP Rent Permits 0 0 0 0 0 1,735
ED-Summary 149,130 297,767,892 26,073,745 148,677 2,151,252,513 188,672,721
202507-Summary 149,130 297,767,892 26,073,745 148,677 2,151,252,513 188,672,721
Overall-Summary 149,130 297,767,892 ve 26,073,745 148,677 2,151,252,513 188,672,721
Page 2 of 4 Run Date: Aug 6,2025
Total Billed Sales-input tab,deferral calc workbook
IFor Internal Use Only
H:\Power Deferrals\Power Deferral 3ournals\2_ID PCA\2025 ID PCA\Cognos Reports\202507 Revenue By Revenue Class ID.xlsx 8/6/209Ye 111.23 AM

Q3 2025 ID PCA Quarterly Report
Current Month Journal Entry
Jurisdiction: ID
Revenue Class Revenue Class Desc Town Code Revenue Class Rate Schedule Gross Unbilled kWh Total Unbilled+Basic Charge
01 01 RESIDENTIAL 3800 01 001 47,732,266 $5,279,773
3800 01 012 1,179,861 $152,108
3800 01 022 255,987 $20,802
3800 01 032 185,629 $24,253
3800 21 011 34,637,992 $3,030,746
3800 21 021 2,068,761 $144,245
3800 21 025 5,425,377 $321,250
21 21 FIRM COMMERCIAL 3800 21 031 3,297,865 $345,275
3800 31 011 1,247,355 $104,811
3800 31 021 1,128,209 $79,416
31 FIRM-INDUSTRIAL 3800 31 025 23,332,114 $1,409,106
31 31 FIRM INDUSTRIAL 3800 31 025P 29,298,897 $1,591,187
3800 31 025PG 41,505,000 $1,501,236
31 FIRM-INDUSTRIAL 3800 31 031 808,896 $84,608
01 -Summary
21 -Summary
i - $4,770,365
192,104,207
Unbilled - Deferracl Calc Workbook
G:\CLOSE\202507\Revenue\REVUNBL\REVUNBLD - E\202507 Electric Unbilled.xlsx 8/6/2025PajEjiI35 AM

Q3 2025 ID PCA Quarterly Report
Columbia Basin Hydro Customer Cost Calculations - July 2025
Generation Mid-C Valuation Contract Valuation
Off Mid-C On Mid-C Off Mid-C Busbar
On Peak Peak Total Peak Peak Weighted Total Cost Cumul.Total Price Total Cost Cumul.Total Customer Cost
Date (MWh) (MWh) (MWh) ($/MWh) ($/MWh) ($/MWh) ($000s) Cost($000s) ($/MWh) Daily Delivery($) ($000s) Cost($000s) ($000s)
7/1/2025 1,815 595 2,410 67.94 45.83 62.48 150,574 150,574 43.17 9,135 113,175 113,175 113,175
7/2/2025 1,832 610 2,442 30.45 25.85 29.30 71,545 222,119 43.17 9,135 114,556 227,731 222,119
7/3/2025 1,845 611 2,456 30.45 25.85 29.30 71,966 294,085 43.17 9,135 115,160 342,891 294,085
7/4/2025 1,845 613 2,458 34.47 34.47 34.47 84,727 378,812 43.17 9,135 115,247 458,138 378,812
7/5/2025 1,851 617 2,468 39.17 34.47 38.00 93,776 472,588 43.17 9,135 115,678 573,816 472,588
7/6/2025 1,851 617 2,468 44.89 44.89 44.89 110,789 583,377 43.17 9,135 115,678 689,495 583,377
7/7/2025 1,845 612 2,457 70.72 44.89 64.29 157,953 741,330 43.17 9,135 115,204 804,698 741,330
7/8/2025 1,841 616 2,457 73.71 50.31 67.85 166,699 908,029 43.17 9,135 115,204 919,902 908,029
7/9/2025 1,425 611 2,036 54.56 39.88 50.15 102,108 1,010,137 43.17 9,135 97,029 1,016,931 1,010,137
7/10/2025 1,841 611 2,452 54.41 39.08 50.59 124,053 1,134,190 43.17 9,135 114,988 1,131,918 1,131,918
7/11/2025 1,870 620 2,490 54.96 43.87 52.20 129,981 1,264,171 43.17 9,135 116,628 1,248,547 1,248,547
7/12/2025 1,865 625 2,490 54.96 43.87 52.18 129,925 1,394,096 43.17 9,135 116,628 1,365,175 1,365,175
7/13/2025 1,867 622 2,489 48.84 48.84 48.84 121,563 1,515,659 43.17 9,135 116,585 1,481,760 1,481,760
7/14/2025 1,860 622 2,482 56.23 48.84 54.38 134,960 1,650,619 43.17 9,135 116,283 1,598,043 1,598,043
7/15/2025 1,849 615 2,464 57.68 49.70 55.69 137,220 1,787,839 43.17 9,135 115,506 1,713,548 1,713,548
7/16/2025 1,848 605 2,453 70.70 52.59 66.23 162,464 1,950,304 43.17 9,135 115,031 1,828,579 1,828,579
7/17/2025 1,853 617 2,470 53.43 42.72 50.76 125,366 2,075,670 43.17 9,135 115,765 1,944,344 1,944,344
7/18/2025 1,848 616 2,464 36.03 36.05 36.04 88,794 2,164,464 43.17 9,135 115,506 2,059,850 2,059,850
7/19/2025 1,818 611 2,429 36.03 36.05 36.04 87,533 2,251,997 43.17 9,135 113,995 2,173,845 2,173,845
7/20/2025 1,831 605 2,436 37.30 37.30 37.30 90,863 2,342,860 43.17 9,135 114,297 2,288,142 2,288,142
7/21/2025 1,851 616 2,467 48.92 37.30 46.02 113,524 2,456,383 43.17 9,135 115,635 2,403,777 2,403,777
7/22/2025 1,815 600 2,415 46.55 39.81 44.87 108,370 2,564,754 43.17 9,135 113,390 2,517,167 2,517,167
7/23/2025 1,832 610 2,442 48.50 39.01 46.13 112,654 2,677,408 43.17 9,135 114,556 2,631,723 2,631,723
7/24/2025 1,843 614 2,457 40.56 38.65 40.08 98,485 2,775,893 43.17 9,135 115,204 2,746,927 2,746,927
7/25/2025 1,860 614 2,474 35.38 34.99 35.28 87,293 2,863,186 43.17 9,135 115,937 2,862,864 2,862,864
7/26/2025 1,823 604 2,427 35.38 34.99 35.28 85,634 2,948,820 43.17 9,135 113,908 2,976,773 2,948,820
7/27/2025 1,841 614 2,455 38.73 38.73 38.73 95,082 3,043,902 43.17 9,135 115,117 3,091,890 3,043,902
7/28/2025 1,847 618 2,465 55.56 38.73 51.34 126,548 3,170,450 43.17 9,135 115,549 3,207,439 3,170,450
7/29/2025 1,850 609 2,459 72.76 57.70 69.03 169,741 3,340,191 43.17 9,135 115,290 3,322,729 3,322,729
7/30/2025 1,856 615 2,471 53.85 39.41 50.26 124,191 3,464,382 43.17 9,135 115,808 3,438,537 3,438,537
7/31/20251 1,863 1 621 2,484 1 44.28 1 37.25 1 42.52 105,628 3,570,010,/ 43.17 9,135 116,369 3,554,906 3,554,906
75,787
Actual Cost 3,554,906
Allowed 3,554,906
Adjustment - !a-oa V
H:\Power Deferrals\Power Deferral Journals\2_ID PCA\2025 ID PCA\2025 CBH and Chelan Generation Reports\07)Jul\202507 CBH and Chelan Contract vs Market(PCA)with transmissiorPc9TYsVsx

Q3 2025 ID PCA Quarterly Report
Chelan Hydro Customer Cost Calculations - July 2025
Generation Mid-C Valuation Contract Valuation
Total Diff
[Positive-
On Off Mid-C On Mid-C Off Mid-C Busbar Total Contract
Peak Peak Total Peak Peak Weighted Total Cost Cumul.Total Price Cost Cumul.Total Customer higher than
Date (MWh) (MWh) (MWh) ($/MWh) ($/MWh) ($/MWh) ($000s) Cost($000s) ($/MWh) ($000s) Cost($000s) Cost($000s) Market]
7/1/2025 706 341 1,046 70.70 45.83 62.60 65,484 65,484 62.49 65,360 65,360 65,360 (124)
7/2/2025 624 495 1,119 31.02 25.85 28.73 32,137 97,621 62.49 69,890 135,250 97,621 37,753
7/3/2025 569 559 1,127 31.02 25.85 28.46 32,072 129,693 62.49 70,421 205,671 129,693 38,349
7/4/2025 - 716 716 34.47 34.47 24,681 154,373 62.49 44,740 250,411 154,373 20,059
7/5/2025 764 195 959 39.76 34.47 38.69 37,081 191,454 62.49 59,892 310,303 191,454 22,811
7/6/2025 - 780 780 44.89 44.89 35,014 226,469 62.49 48,739 359,042 226,469 13,725
7/7/2025 527 261 788 73.95 44.89 64.34 50,665 277,134 62.49 49,207 408,249 277,134 (1,458)
7/8/2025 548 324 871 76.64 50.31 66.86 58,236 335,370 62.49 54,425 462,674 335,370 (3,811)
7/9/2025 398 252 650 56.39 39.88 50.00 32,473 367,843 62.49 40,584 503,259 367,843 8,111
7/10/2025 396 248 644 56.33 39.08 49.70 31,979 399,822 62.49 40,209 543,468 399,822 8,230
7/11/2025 483 277 759 56.35 43.87 51.80 39,319 439,141 62.49 47,427 590,895 439,141 8,108
7/12/2025 499 424 922 56.35 43.87 50.62 46,669 485,810 62.49 57,612 648,506 485,810 10,942
7/13/2025 - 1,004 1,004 48.84 48.84 49,011 534,821 62.49 62,704 711,211 534,821 13,693
7/14/2025 693 299 992 57.15 48.84 54.65 54,184 589,005 62.49 61,954 773,165 589,005 7,771
7/15/2025 605 266 871 58.68 49.70 55.94 48,722 637,726 62.49 54,425 827,590 637,726 5,703
7/16/2025 611 404 1,015 72.96 52.59 64.85 65,825 703,551 62.49 63,423 891,013 703,551 (2,402)
7/17/2025 773 417 1,189 54.77 42.72 50.55 60,103 763,654 62.49 74,295 965,308 763,654 14,193
7/18/2025 678 396 1,074 36.03 36.05 36.04 38,704 802,358 62.49 67,109 1,032,418 802,358 28,405
7/19/2025 493 370 863 36.03 36.05 36.04 31,101 833,459 62.49 53,925 1,086,343 833,459 22,824
7/20/2025 - 856 856 37.30 37.30 31,929 865,388 62.49 53,488 1,139,830 865,388 21,559
7/21/2025 675 275 950 50.37 37.30 46.58 44,232 909,620 62.49 59,330 1,199,160 909,620 15,098
7/22/2025 622 385 1,007 47.39 39.81 44.49 44,780 954,400 62.49 62,892 1,262,052 954,400 18,112
7/23/2025 760 345 1,105 49.69 39.01 46.35 51,198 1,005,598 62.49 69,015 1,331,067 1,005,598 17,817
7/24/2025 568 277 845 40.80 38.65 40.09 33,860 1,039,458 62.49 52,769 1,383,836 1,039,458 18,909
7/25/2025 722 309 1,031 35.43 34.99 35.30 36,375 1,075,833 62.49 64,391 1,448,228 1,075,833 28,017
7/26/2025 545 261 806 35.43 34.99 35.29 28,424 1,104,257 62.49 50,332 1,498,560 1,104,257 21,908
7/27/2025 - 830 830 38.73 38.73 32,127 1,136,383 62.49 51,832 1,550,391 1,136,383 19,705
7/28/2025 476 229 705 57.66 38.73 51.51 36,315 1,172,699 62.49 44,052 1,594,444 1,172,699 7,737
7/29/2025 561 270 830 74.64 57.70 69.14 57,386 1,230,084 62.49 51,863 1,646,307 1,230,084 (5,523)
7/30/2025 705 377 1,082 55.66 39.41 50.00 54,078 1,284,163 62.49 67,578 1,713,885 1,284,163 13,500
7/31/2025 852 377 1,229 45.16 37.25 42.73 52,497 1,336,660 V 62.49 76,763 1,790,648 1,336,660 24,267
28,657 453,989
Actual Cost 11790,648
Allowed 1,336,660
Adjustment 453,989 R-os V
H:\Power Deferrals\Power Deferral Journals\2_ID PCA\2025 ID PCA\2025 CBH and Chelan Generation Reports\07)Jul\202507 CBH and Chelan Contract vs Market(PCA)with transmission costs.xlsR age 15

Q3 2025 ID PCA Quarterly Report
2023 WA Compliance Year V vintage vintage Compliance Qty Lost Rev
VINTAGE--> Jan-22 Feb-22 Mar-22 Apr-22 May-22 Jun-22 Jul-22 Aug-22 Sep-22 Oct-22 Nov-22 Dec-22 Jan-23 Feb-23 Mar-23 Apr-23 May-23 Jun-23 Jul-23 Aug-23 Sep-23 Oct-23 Nov-23 Dec-23 Total 2022 2023 RPS/CETA CCA Total ID share ID$ avg price
Qty for 2023 RPS&CETA Boulder Solar 485 0 485 167 667 $4.00
Boulder Solar 18 28 44 50 62 63 67 43 42 37 19 12 485 - 485 CBHP 5,411 11,095 16,506 5,676 6,811 $1.20
CBHP - - - - - 340 2,067 2,061 280 663 - - 5,411 5,411 Chelan PUD 0 223,743 223,743 76,961 92,354 $1.20
Chelan PUD - - - - - - - - - - - - - - - Clark Fork 1,218,646 892,445 2,111,091 725,849 871,019 $1.20
Clark Fork 90,073 87,317 51,571 64,180 333,085 157,920 107,863 67,836 47,129 63,776 57,858 90,038 1,218,646 1,218,646 Douglas PUD 180,946 85,419 266,365 91,635 109,962 $1.20
Douglas PUD - - - - - - 37,775 41,157 18,338 20,583 34,256 28,837 180,946 180,946 Grant PUD 140,152 80,508 220,660 75,898 91,078 $1.20
Grant PUD - - - - 21,060 21,278 25,372 12,603 14,425 22,799 22,615 140,152 140,152 Kettle 264,240 1,949 266,189 91,554 409,824 $4.48
Kettle 17,803 24,488 19,668 6,550 - 11,649 24,619 24,325 21,518 19,882 18,749 22,327 211,578 - 211,578 LL/LF 254,800 90,285 345,085 118,667 142,401 $1.20
LL/LF 35,598 23,211 24,288 30,529 38,926 22,181 9,887 7,085 6,689 11,645 18,195 26,566 254,800 254,800 Palouse 328,222 58,115 386,337 132,845 525,890 $3.96
Palouse 9,165 12,930 18,892 18,287 21,949 506 24,773 29,732 35,796 22,289 18,102 14,757 10,273 12,495 13,108 14,271 12,091 16,477 22,329 328,222 106,502 221,720 Rattlesnake 279,067 70,990 350,057 120,387 479,523 $3.98
Rattlesnake - 16,565 - - 4,467 - 18,238 8,097 34,196 26,846 22,314 21,382 16,403 18,697 21,444 19,341 16,599 16,546 17,932 279,067 39,270 239,797 Upp Spo 146,624 41,192 187,816 64,586 258,346 $4.00
Upp Spo 25,168 17,674 15,624 15,167 15,021 11,604 4,812 2,841 4,749 7,589 12,915 13,460 146,624 - 146,624 TOTAL 2,818,593 1,555,741 4,374,334 1,504,2261 2,987,874 $1.99
2,765,931 145,772 2,620,159
CBHP RECs never received,therefore couldn't have marketed--> 4,162
2023 CETA compliance target--> 2,624,321
city for 2023 CCA
Boulder Solar - - - - -
CBHP 4,180 2,098 1,454 2,625 738 - - 11,095 11,095
Chelan PUD 10,006 8,633 20,996 12,963 30,448 30,453 34,486 18,120 15,568 31,575 10,495 223,743 223,743
Clark Fork 50,546 51,971 53,321 78,577 185,075 202,002 63,639 31,285 49,518 40,274 39,840 46,397 892,445 - 892,445
Douglas PUD - - 25,691 22,104 2,100 35,405 119 - - - - - 85,419 85,419
Grant PUD 2,594 10,778 17,628 13,416 34,747 666 679 80,508 80,508
Kettle - 63 - 666 658 - 562 - - - 1,949 1,949
LL/LF 1,121 4,172 16,314 24,795 2,152 11,115 3,746 2,680 3,281 4,108 9,021 7,780 90,285 - 90,285
Palouse 125 1,101 7,711 9,497 193 5,371 4,492 4,455 7,373 4,520 8,624 4,653 58,115 58,115
Rattlesnake 138 1,682 8,764 11,701 424 8,620 6,347 6,422 9,375 5,602 8,660 3,255 70,990 70,990
Upp Spo 2,128 1,546 14,055 5,673 1,247 4,525 1,723 904 1,747 1,656 5,142 846 41,192 - 41,192
1,555,741 - 1,555,741
Add'1 qty for 2022 CETA not included in last year's adjustment
Kettle 8,801 18 40 196 19,418 26 24,163 52,662 52,662 -
Total RECs
Boulder Solar - - - - - - - 18 28 44 50 62 63 67 43 42 37 19 12 485 - 485
CBHP - - - - 4,520 4,165 3,515 2,905 1,401 - - 16,506 16,506
Chelan PUD 10,006 8,633 20,996 12,963 30,448 30,453 34,486 18,120 15,568 31,575 10,495 223,743 223,743
Clark Fork - - - - - - - - - - - - 140,619 139,288 104,892 142,757 518,160 359,922 171,502 99,121 96,647 104,050 97,698 136,435 2,111,091 - 2,111,091
Douglas PUD - - 25,691 22,104 2,100 35,405 37,894 41,157 18,338 20,583 34,256 28,837 266,365 266,365
Grant PUD 2,594 10,778 17,628 13,416 34,747 21,726 21,957 25,372 12,603 14,425 22,799 22,615 220,660 220,660
Kettle 8,801 18 40 196 19,418 26 24,163 17,803 24,488 19,668 6,613 - 12,315 25,277 24,325 22,080 19,882 18,749 22,327 266,189 52,662 213,527
LL/LF - - - - - - - - - - - - 36,719 27,383 40,602 55,324 41,078 33,296 13,633 9,765 9,970 15,753 27,216 34,346 345,085 - 345,085
Palouse 9,165 12,930 18,892 18,287 21,949 506 24,773 29,857 36,897 30,000 27,599 14,950 15,644 16,987 17,563 21,644 16,611 25,101 26,982 386,337 106,502 279,835
Rattlesnake - 16,565 - - 4,467 - 18,238 8,235 35,878 35,610 34,015 21,806 25,023 25,044 27,866 28,716 22,201 25,206 21,187 350,057 39,270 310,787
Upp Spo - 27,296 19,220 29,679 20,840 16,268 16,129 6,535 3,745 6,496 9,245 18,057 14,306 187,816 - 187,816
4,374,334 198,434 4,175,900
Price Amerex REC Pricing,6/9/25
Boulder Solar $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 WECC Solar,$0.10 above Bid
CBHP $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 WECC Hydro,$0.10 above Bid
Chelan PUD $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20
Clark Fork $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 "
Douglas PUD $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 "
Grant PUD $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 "
Kettle $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 CA PCC-3,$0.10 above Bid
LL/LF $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 $1.20 WECC Hydro,$0.10 above Bid
Palouse $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 CA PCC-3,$0.10 above Bid
Rattlesnake $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $3.85 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 "
Upp Spo M $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00 $4.00
Kettle adjust. $6.41 $6.41 $6.41 $6.41 $6.41 $6.41 $6.41 $6.41 $6.41 $6.41 $6.41 $6.41
System
Boulder Solar - - - - - - - - - - - - 72 112 176 200 248 252 268 172 168 148 76 48 1,940 - 1,940
CBHP - - - - - 5,424 4,998 4,218 3,486 1,681 - - 19,807 19,807
Chelan PUD - 12,007 10,360 25,195 15,556 36,538 36,544 41,383 21,744 18,682 37,890 12,594 268,492 268,492
Clark Fork 168,743 167,146 125,870 171,308 621,792 431,906 205,802 118,945 115,976 124,860 117,238 163,722 2,533,309 2,533,309
Douglas PUD - - - - - - - - - - - - - - 30,829 26,525 2,520 42,486 45,473 49,388 22,006 24,700 41,107 34,604 319,638 - 319,638
Grant PUD 3,113 12,934 21,154 16,099 41,696 26,071 26,348 30,446 15,124 17,310 27,359 27,138 264,792 264,792
Kettle 56,414 115 256 1,256 124,469 167 154,885 71,212 97,952 78,672 26,452 - 49,260 101,108 97,300 88,320 79,528 74,996 89,308 1,191,671 337,563 854,108
LL/LF - - - - - - - 44,063 32,860 48,722 66,389 49,294 39,955 16,360 11,718 11,964 18,904 32,659 41,215 414,102 - 414,102
Palouse - - - 35,285 - - 49,781 72,734 70,405 84,504 1,948 95,376 119,428 147,588 120,000 110,396 59,800 62,576 67,948 70,252 86,576 66,444 100,404 107,928 1,529,373 410,033 1,119,340
Rattlesnake - 63,775 - - 17,198 - 70,216 32,940 143,512 142,440 136,060 87,224 100,092 100,176 111,464 114,864 88,804 100,824 84,748 1,394,338 151,190 1,243,148
Upp Spo - - - - - - - 109,184 76,880 118,716 83,360 65,072 64,516 26,140 14,980 25,984 36,980 72,228 57,224 751,264 - 751,264
PT Ratio 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.36% 34.47% 34.47% 34.47% 34.E%J 8,688,726 898,786 7,789,940
$ 1.99 OD
Idaho$ 19,384 - - 12,124 - - 39,057 25,080 24,623 77,712 727 110,116 188,552 237,424 239,468 227,458 324,084 295,179 216,868 189,072 174,491 164,780 208,468 213,207 $2,987,874.44V $ 308,823 $ 2,679,052
adj from last year 19,384 40 88 432 42,768 57 53,218 © $ 115,987 $ 115,987 -
C:\Users\jhh8966\AppData\Local\Microsoft\Windows\INetCache\Content.Outlook\EDBSUH9Y\Idaho JE lost revenue from WA compliance.xlsx2023 CY Page 16

Q3 2025 ID PCA Quarterly Report
Hossack,Jennifer
From: Reid, Scott
Sent: Tuesday,July 29, 2025 2:28 PM
To: Hossack,Jennifer; Brandon,Annette; Drake, Chris
Subject: RE: ID Lost Revenuejournal entry calc(DRAFT)
Attachments: Idaho JE lost revenue from WA compliance.xlsx
James came up with a lower 2023 CCA obligation of 1,555,741 allowances.
This year's entry is$2.98M vs. last year's$2.76M.
Scott Reid
Resource Marketing Manager
APu 1 i'ISTAN
1411 E Mission MCS-7
Spokane,WA 99202
P 509.495.4893
http://www.avistautilities.com
1
Page 17

Q3 2025 ID PCA Quarterly Report
Avista Corporation Journal Entry Printed 08/04/2025 at 10:19 AM
Journal: 240-EIM DEFERRAL Effective Date: 202507
Team: Energy Delivery Accounting Last Saved by: Ian Williams Last Update:08/04/2025 10:19 AM
Type: C Submitted by: Ian Williams Approval Requested:08/04/2025 10:19 AM
Category: DJ Approved by:
Currency: USD
Seq. Co. FERC Ser. Jur. S.I. Debit Credit Comment
10 001 431230-INTEREST ON REG DEFERRALS-ST ED WA DL 1,837.34 0.00 Provisional EIM WA-202507 Interest
20 001 229030-ACCUM PROV RATE REFUND-EIM ED WA DL 16,964.14 0.00 Provisional EIM WA-202507 Deferral
CAP
30 001 184057-CLEARING ACCT-ENERGY DLIVERY ZZ ZZ DL 0.00 18,801.48 Provisional EIM WA-202507 Deferral
ACCT
Totals: 18,801.48 18,801.48
Seq. Project Task Exp. Org Quantity Co. FERC Ser. Jur.
10 03805834-EIM Deferral-ID 182334-Regulatory Asset-EIM 885 D57- (29,129.96) 001 184057-CLEARING ACCT-ENERGY ZZ ZZ
Miscellaneous Misc DLIVERY ACCT
Comment:EIM Deferral ID-202507 Amortization
20 03805834-EIM Deferral-ID 407334-Amort of EIM Defer 885 D57- 29,129.96 001 184057-CLEARING ACCT-ENERGY ZZ ZZ
Miscellaneous Misc DLIVERY ACCT
Comment:EIM Deferral ID-202507 Amortization
A
30 03805834-EIM Deferral-ID 407434-EIM Deferred O&M 885 D57- © (31,145.70)./001 182386 REGULATORY ASSET ID ED ID
Miscellaneous Misc PCA DEFERRAL 2
Comment:EIM PCA Deferral ID-202507
40 02807414-EIM Interest Deferral-WA 407439-Amort EIM Defferal 885 D57- (18,801.48) 001 184057-CLEARING ACCT-ENERGY ZZ ZZ
Miscellaneous Misc DLIVERY ACCT
Comment:Provisional EIM WA-202507 Amortization
Total: (49,947.18)
Explanation:
To record EIM Deferred costs in accordance with IPUC Order No.34606-
Post costs of which 90%are to be deferred through the PCA.
Page 1 of 2
Page 18

Q3 2025 ID PCA Quarterly Report
DJ475-Washington REC Deferral -Account 186323
The rate is based on WA Rate Order for REC deferral
Interest will be accrued monthly and compounded semi-annually.
Interest is calculated using the prior month ending balance plus 1/2 month of current month charges times the current monthly interest rate
Account 186323 ED WAS 186323 RECON
Balance before Monthly Interest End Balance End Balance with GL Wand
Month Ending Interest Balance Transfer Deferral WA 1-937 RPS&CETA Interest Rate Interest Adjustments before interest Interest Balance Variance
202501
202502
202503
202504
202505
202506
202507 9,533.41 2,987,874. 0.54259% 16,237.77 2,997,407.85 3,013,645.62 (3,013,645.62)
202508 recorded on NS3009
202509
202510
202511
202512
current month entry 9,533.41 1 G.2-
202507 UPDATE DATE TO CALC JET ENTRY
JET ENTRY: DR CR
186323 ED WA 16,237.77 Misc Def Debit-WA Rec 2
419600 ED WA 16,237.77 Interest Expense on Rec Deferral
186323 ED WA 9,533.41 Misc Def Debit-WA Rec 2
557322 ED WA 9,533.41 Def Power Supply Exp-RECs
Page 19
H:\Power Deferrals\Power Deferral Journals\3 REC Deferral\2025 DJ475 WA REC 186323 Def 202507-202606 V 8/5/2025 3:34 PM

Q3 2025 ID PCA Quarterly Report
AVISTA UTILITIES
POWER COST ADJUSTMENT REPORT
THIRD QUARTER 2025
MONTH OF AUGUST
Page 20

Q3 2025 ID PCA Quarterly Report
Avista Corporation Journal Entry Printed 09/06/2025 at 10:31 AM
Journal: 480-ID PCA Effective Date: 202508 0
Team: Resource Accounting Last Saved by: Jennifer Hossack Last Update:09/06/2025 10:23 AM
Type: C Submitted by: Jennifer Hossack Approval Requested:09/06/2025 10:31 AM
Category: DJ Approved by:
Currency: USD
e 9/6/25
Prepared by Jennifer Hossack Date
t}ltify Tal-sons 9/7/25
Reviewed by Date
Approved for Entry Date
Corporate Accounting use Only
Page 2 of 2
Page 21

Q3 2025 ID PCA Quarterly Report
Avista Corporation Journal Entry Printed 09/06/2025 at 10:31 AM
Journal: 480-ID PCA Effective Date: 202508
Team: Resource Accounting Last Saved by: Jennifer Hossack Last Update:09/06/2025 10:23 AM
Type: C Submitted by: Jennifer Hossack Approval Requested:09/06/2025 10:31 AM
Category: DJ Approved by:
Currency: USD
Seq. Co. FERC Ser. Jur. S.I. Debit Credit Comment
5 001 557380-IDAHO PCA-DEF ED ID DL 0.00 901,894.00,/Current Deferral Expense-PCA
10 001 182386-REGULATORY ASSET ID PCA ED ID DL 901,894.00 v 0.00 Current Deferral Reg Asset-PCA
DEFERRAL 2
20 001 182386-REGULATORY ASSET ID PCA ED ID DL 0.00 7,600.00,'Interest Expense-PCA
DEFERRAL 2
30 001 431600-INTEREST EXPENSE ENERGY ED ID DL 7,600.00,' 0.00 Interest Exp on 182386
DEFERRALS
60 001 182385-REGULATORY ASSET ID PCA ED ID DL 0.00 33,113.00vPending Deferral Interest Exp 182385
DEFERRAL 1
70 001 431600-INTEREST EXPENSE ENERGY ED ID DL 33,113.00V 0.00 Pending Deferral Interest Exp 182385
DEFERRALS
80 001 182387-REGULATORY ASSET ID PCA ED ID DL 0.00 11,545.00VAmortizing Interest Expense
DEFERRAL 3
90 001 431600-INTEREST EXPENSE ENERGY ED ID DL 11,545.00 v 0.00 Amortizing Interest Expense 182387
DEFERRALS
100 001 182387-REGULATORY ASSET ID PCA ED ID DL 657,988.00 0 0.00 Amortizing Deferral 182387
DEFERRAL 3
110 001 557390-IDAHO PCA AMT ED ID DL 0.00 657,988.00vAmortizing Deferral 182387
Totals: 1,612,140.00 1,612,140.00
Explanation:
Record deferral of power costs in Idaho,amortization of existing balance,and
interest&DFIT entries.
Page 1 of 2
Page 22

Q3 2025 ID PCA Quarterly Report
Idaho Power Cost Adjustment(PCA)Deferral Balance-Current Year Bucket
Interest compounds and is calculated monthly
Interest Rate
2024 0.41667%
2025 0.416679/6
Balance Deferral- Interest
Month Ending Account Be .Balance Transfer Surd Reb. Ad'ustments Interest Ad'ustments Balance with Interest GLW Balance Recon Adjustment Notes
12/31/2024 182385 (7,714,835)
1/31/2025 182385 7,714,835 1,447,025 28,985 32,145 9,165,020 9,165,020 DJ240 EIM Deferral
2/28/2025 182385 9,165,020 1,165,452 23,785 38,188 8,013,971 8,013,971 DJ240 EIM Deferral
3/31/2025 182385 8,013,971 197,621 22,795 33,392 8,222,189 8,222,189 DJ240 EIM Deferral
4/30/2025 182385 8,222,189 1,072,522 28,878 34,259 9,300,092 9,300,091 1 DJ240 EIM Deferral
5/31/2025 182385 9,300,092 204,530 26,665 38,751 9,516,707 9,5161707 DJ240 EIM Deferral
6/30/2025 182385 (9,516,707) 1,606,715 35,666 (39,653) (7,913,979) (7,913,979) DJ240 EIM Deferral
This account moves to the Pendin tab
6/30/2025 182386 This account moves from the Pending tab
7/31/2025 182386 1,132,826 2,956,729 0 1,823,903 1,823,903 WA 1-937&CETA Compliance&EIM Deferral
8/31/2025 182386 1,823,903.00 a-oz 901,894 A 40,988 7,600 888,621.00 1,782,915 894,294
9/30/2025 182386
10/31/2025 182386
11/30/2025 182386
12/31/2025 182386
901,894 (7,600)
Entry:
Debit Credit
557380 ED ID 901,89401daho PCA-Def
182386 ED ID 901,894 V Regulatory Asset ID PCA Deferral
431600 ED ID 7,600 V Interest Expense Energy Deferrals
182386 ED ID 7,600VRegulatory Asset ID PCA Deferral
Page 23
H:\Power Deferrals\Power Deferral Joumals\2 ID PCA\2025 ID PCA\2025 DJ480 ID PCA.xlsx

Q3 2025 ID PCA Quarterly Report
Idaho Power Cost Adjustment(PCA)Deferral Balance-Pending Bucket
Interest compounds and is calculated monthly
Interest Rate
20241 0.41667%
20251 0.41667%
Balance Interest Balance with
Month Ending Account Beg.Balance Transfer Activity Adjustments Interest Adjustments Interest GLW Balance Recon Adjustment Notes
12/31/2024 182386
1/31/2025 182386
2/28/2025 182386
3/31/2025 182386
4/30/20251 182386
5/31/20251 182386
6/30/2025 182386
This account moves to the Current Year tab
6/30/2025 182385 This account moves from the Current Year tab (7,913,979)
7/31/2025 182385 7,913,979 (32,975)1 1 (7,946,954 7,946,954 -
8/31/2025 182385 (7,946,954) v (33,113) o (7,980,067) (7,946,954) 33,113
9/30/2025 182385
10/31/2025 182385
This account moves to the Amortizing tab
10/31/2025 182387 This account moves from the Amortizing tab
11/30/2025 182387
12/31/2025 182387
(33,113)
Entry:
Debit Credit
431600 ED ID 33,113,/ Interest Exp Energy Deferrals
182385 ED ID 33,113 vRegulatory Asset ID PCA Deferral
H:\Power Deferrals\Power Deferral Journals\2 ID PCA\2025 ID PCA\2025 DJ480 ID PCA.xlsx Page 24

Q3 2025 ID PCA Quarterly Report
Idaho Power Cost Adjustment(PCA)Deferral Balance-Amortizing Bucket
Interest compounds and is calculated monthly
Interest Rate
20241 0.41667%
20251 0.41667%
Balance Interest Balance with
Month Ending Account Beg. Balance Transfer Amortization Adjustments Interest Adjustments Interest GLW Balance Recon Adjustment Notes
12/31/2024 182387 (7,197,201)
1/31/2025 182387 (7,197,201) 766,605 (29,988.58) (6,460,585) (6,460,585)
2/28/2025 182387 6,460,585 757,753 26,919.32 5,729,751 5,729,751
3/31/2025 182387 (5,729,751) 671,679 (23,874.15) (5,081,946) (5,081,946)
4/30/2025 182387 5,081,946 625,760 21,174.94 4,477,361 4,477,361
5/31/2025 182387 (4,477,361) 542,748 (18,655.82) (3,953,269) (3,953,269)
6/30/2025 182387 3,953,269 581,283 16,472.09 3,388,458 3,388,458
7/31/2025 182387 (3,388,458) 631,802 (14,119) (2,770,775) (2,770,775)
8/31/2025 182387 2,770,775 657,988 11,545 2,124,332 2,770,775 646,443
9/30/2025 182387
10/31/2025 182387
This account moves to the Pending tab
10/31120251 182385 This account moves from the Pending tab
11/30/20251 1823851 1 0
12131120251 182385
657,988
Entry:
Debit Credit
182387 ED ID 657,988 V Regulatory Asset ID PCA Deferral
557390 ED ID 657,988,/Idaho PCA Amt
431600 ED ID 11,545 Interest Expense Energy Deferrals
182387 ED ID 11,545vRegulatory Asset ID PCA Deferral
H:\Power Deferrals\Power Deferral Journals\2 ID PCA\2025 ID PCA\2025 DJ480 ID PCA.xlsx Page 25

Q3 2025 ID PICA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO POWER COST DEFERRALS
Line
No. IDAHO ACTUALS TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25
1 555 Purchased Power $140,457,525 $14,649,944 $22,918,792 $17,154,312 $15,506,870 $16,498,614 $17,744,546 $19,209,958 $16,654,111 $120,378 $0 $0 $0
2 447 Sale for Resale ($130,186,559) ($15,815,928) ($17,283,171) ($18,540,183) ($16,913,483) ($14,491,131) ($16,307,443) ($17,937,409) ($12,794,325) ($103,486) $0 $0 $0
3 501 Thermal Fuel $26,734,344 $3,455,873 $4,522,795 $3,752,557 $1,697,225 $1,525,413 $2,568,207 $4,607,181 $4,605,093 $0 $0 $0 $0
4 547 CT Fuel $71,372,274 $13,795,379 $12,944,613 $10,184,136 $5,401,423 $3,985,276 $8,335,950 $7,792,958 $8,932,539 $0 $0 $0 $0
5 456 Transmission Rev ($21,583,931) ($2,968,699) ($2,980,575) ($2,877,392) ($2,606,548) ($2,690,461) ($2,446,343) ($2,610,094) ($2,403,819) $0 $0 $0 $0
6 565 Transmission Exp $19,418,528 $2,251,109 $2,251,996 $2,656,824 $2,476,343 $2,399,160 $2,395,608 $2,489,270 $2,498,218 $0 $0 $0 $0
7 537 MT Invasive Species Exp $517,776 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $0 $0 $0 $0
8 557 Expenses $203,393 $7,057 $8,599 $53,596 $57,166 $69,241 $3,779 $2,102 $1,853 $0 $0 $0 $0
9 Adjusted Actual Net Expense $106,916,458 $15,439,457 $22,447,771 $12,448,572 $5,683,718 $7,360,834 $12,359,026 $13,618,688 $17,558,392✓ $16,892 $0 $0 $0
AUTHORIZED NET EXPENSE-SYSTEM YTD Janl25 Feb/25 Mar/25 Apr/25 Mayl25 Jun/25 Jul/25 Aug/25 Sep/25 Octl25 Novl25 Dec/25
10 555 Purchased Power $ 50,384,588 7,435,932 7,069,211 7,433,801 5,672,869 5,579,483 5,419,545 5,937,659 5,836,088 5,942,565 6,184,512 6,489,810 6,556,792.00
11 447 Sale for Resale $ (34,427,764) (2,316,991) (1,936,564) (2,540,468) (4,230,873) (3,489,856) (5,862,698) (9,557,120) (4,493,194) (7,072,562) (3,997,529) (2,672,014) (4,453,080.00)
12 501 Thermal Fuel $ 20,192,325 3,151,777 2,749,966 2,896,333 2,060,445 1,526,412 1,782,225 2,879,162 3,146,005 3,033,757 2,874,156 2,395,831 3,087,726.00
13 547 CT Fuel $ 45,654,416 8,942,104 7,474,530 5,068,911 4,095,763 2,284,385 3,117,887 6,693,265 7,977,571 8,729,385 8,223,214 8,133,493 10,790,239.00
14 456 Transmission Revenue $ (15,961,214) (1,634,727) (1,811,669) (1,891,560) (1,715,927) (2,123,305) (2,306,697) (2,267,860) (2,209,469) (1,714,509) (1,711,129) (1,937,530) (2,146,621.00)
15 565 Transmission Expense $ 11,519,176 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897.00
16 90%Palouse Wind and Rattlesnake Flats $ 19,542,000 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750.00
17 Remove Columbia Basin Hydro Transmission Project$ (671,336) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917.00)
18 Gas Liquids Revenue/Acct 456 Other Rev Sep-Dec $ (4,874,704) (633,351) (664,038) (880,329) (385,474) (657,028) (615,703) (524,310) (514,471) (290,007) (311,801) (548,421) (265,977.00)
19 Montana Invasive Species Expense $ 1,073,336 134,167 134,167 134,167 134,167 134,167 134,167 134,167 134,167 134,167 134,167 134,167 134,167.00
20 Settlement Adjustments/Other Exp 557 Sep-Dec $ 421,088 52,636 52,636 52,636 52,636 52,636 52,636 52,636 52,636 52,636 52,636 52,636 52,636.00
21 Authorized Net Expense $92,851,911 18,930,277 16,866,969 14,072,221 9,482,336 7,105,624 5,520,092 7,146,329 13,728,063✓ 12,614,162 15,246,956 15,846,702 17,554,612.00
22 Actual-Authorized Net Expense $14,064,547 ($3,490,820) $5,580,802 ($1,623,649) ($3,798,618) $255,210 $6,838,934 $6,472,359 $3,830,329✓ ($12,597,270)
23 Resource Optimization ($538,397) $209,703 ($101,488) $502,625 ($359,215) ($146,870) ($41,017) ($833,877) $231,742✓ $0 $0 $0 $0
24 Adjusted Actual-Authorized Net Expense $13,526,150 ($3,281,117) $5,479,314 ($1,121,024) ($4,157,833) $108,340 $6,797,917 $5,638,482 $4,062,071✓ ($12,597,270)
25 Idaho Allocation 34.47% 34.47% 34.47% 34.47% 34.47% 34.47% 34.47% 34.47%✓ 34.47% 34.47% 34.47% 34.47
26 Idaho Share $4,662,465 ($1,131,001) $1,888,720 ($386,417) ($1,433,205) $37,345 $2,343,242 $1,943,585 $1,400,196✓ ($4,342,279)
27 Idaho 100%Activity(Clearwater) ($642,624) ($70,325) ($91,841) ($73,997) ($72,895) ($85,016) ($81,355) ($81,772) ($85,423)1/ $0 $0 $0 $0
ID Load Change Adjustment(+)Surcharge;(-) R-03
28 Rebate ($1,925,187) ($406,480) ($501,932) $240,835 $314,409 ($179,585) ($476,648) ($603,117) ($312,669)✓ $9,742,989
29 Net Power Cost Increase(+)Surcharge;(-) $2,094,654
Rebate ($1,607,806) $1,294,947 ($219,579) ($1,191,691) ($227,256) $1,785,239 $1,258,696 $1,002,104✓ $5,400,710
30
90%of Net Power Cost Change $1,885,189 ($1,447,025) $1,165,452 ($197,621) ($1,072,522) ($204,530) $1,606,715 $1,132,826 - $901,894✓ $4,860,639
R-02
31 Acct 557380 Entry;(+)Rebate,(-)Surcharge ($1,885,189) $1,447,025 ($1,165,452) $197,621 $1,072,522 $204,530 ($1,606,715) ($1,132,826) ($901,894)✓ ($4,860,639)
32 Energy Imbalance Market Incremental O&M Costs $265,453 $32,205 $26,428 $25,328 $32,087 $29,628 $39,629 $34,606 $45,542 $0 $0 $0 $0
33 90%of Energy Imbalance Market $238,907 $28,985 $23,785 $22,795 $28,878 $26,665 $35,666 $31,145 $40,988 $0 $0 $0 $0
34 Acct 407434 Entry;(+)Rebate,(-)Surcharge ($238,907) ($28,985) ($23,785) ($22,795) ($28,878) ($26,665) ($35,666) ($31,145) ($40,988) $0 $0 $0 $0
35 Total Deferral Balance Sheet Entry ($2,124,096) ($1,418,040) $1,189,237 ($174,826) ($1,043,644) ($177,865) $1,642,381 $1,163,971 $942,882 $4,860,639 $0 $0 $0
Page�A-1 of 4
2025 WA ID Actual Deferrals.xlsx-9/5/2025

Q3 2025 ID PICA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO DEFERRED POWER COST CALCULATION-ACTUAL SYSTEM POWER SUPPLY EXPENSES
Line
No. TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25
555 PURCHASED POWER
1 Other Short-Term Purchases $21,726,726 $2,347,807 $9,949,684 $1,726,673 ($17,697) $543,667 $2,077,148 $3,227,094 $1,751,972 $120,378 $0 $0 $0
2 Chelan County PUD(not in settlement) $11,152,648 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $0 $0 $0 $0
3 Chelan County PUD(in settlement) $14,325,184 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $0 $0 $0 $0
4 Douglas County PUD(Wells Settlement) $492,100 $37,007 $27,060 $36,071 $51,732 $55,201 $51,782 $111,264 $121,983 $0 $0 $0 $0
5 Douglas County PUD(Wells) $755,112 $94,389 $94,389 $94,389 $94,389 $94,389 $94,389 $94,389 $94,389 $0 $0 $0 $0
6 Grant County PUD(Priest RapidefWanapum) $22,553,644 $2,817,090 $2,817,090 $2,817,090 $2,834,014 $2,817,090 $2,817,090 $2,817,090 $2,817,090 $0 $0 $0 $0
7 Bonneville Power Admin.(WNP-3)' 573-Enter $0
8 Inland Power&Light-Deer Lake $6,924 $929 $1,062 $1,156 $767 $740 $776 $686 $808 $0 $0 $0 $0
9 Small Power $772,870 $91,551 $67,808 $128,480 $143,116 $121,014 $104,932 $82,084 $33,885 $0 $0 $0 $0
10 Clearwater Wind III,LLC $7,584,869 $1,327,691 $986,871 $1,071,271 $901,880 $1,055,322 $773,983 $734,198 $733,653 $0 $0 $0 $0
11 City of Spokane-Upriver $1,684,265 $322,436 $129,608 $422,448 $356,808 $358,390 $94,575 $0 $0 $0 $0 $0 $0
12 City of Spokane-Waste-to-Energy $4,362,981 $684,124 $619,347 $518,361 $477,857 $335,476 $500,920 $631,303 $595,593 $0 $0 $0 $0
13 East,South,Quincy Columbia Basin Irrigation Dist $14,870,943 $0 $0 $484,065 $2,269,922 $3,061,573 $3,077,978 $3,271,725 $2,705,680 $0 $0 $0 $0
14 Rathdrum Power,LLC(Lancaster PPA) $18,281,375 $2,164,734 $2,373,653 $2,327,189 $2,085,304 $1,964,612 $2,457,245 $2,429,571 $2,479,067 $0 $0 $0 $0
15 Palouse Wind $12,963,821 $969,296 $1,601,821 $2,697,346 $1,914,119 $1,684,273 $1,459,184 $1,517,921 $1,119,861 $0 $0 $0 $0
16 Rattlesnake Flat,LLC $7,419,950 $390,336 $753,072 $1,485,098 $1,140,611 $1,038,716 $904,696 $859,218 $848,203 $0 $0 $0 $0
17 WPM Ancillary Services $876,117 $111,115 $194,678 $88,561 $87,492 $83,461 $99,714 $106,637 $104,459 $0 $0 $0 $0
18 Non-Mon.Accruals $627,996 $106,710 $117,920 $71,385 ($18,173) $99,961 $45,405 $142,049 $62,739 $0 $0 $0 $0
19 Total 555 Purchased Power $140,457,525 $14,649,944 $22,918,792 $17,154,312 $15,506,870 $16,498,614 $17,744,546 $19,209,958 $16,654,111 $120,378 $0 $0 $0
555 PURCHASED POWER
555000 $140,516,665 $13,866,745 $21,620,393 $17,220,716 $17,484,550 $17,494,009 $17,252,770 $19,066,877 $16,510,605 $0 $0 $0 $0
555030 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555200 ($100,880) $0 $0 $0 ($100,880) $0 $0 $0 $0 $0 $0 $0 $0
555312 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555313 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555380 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555550 $627,996 $106,710 $117,920 $71,385 ($18,173) $99,961 $45,405 $142,049 $62,739 $0 $0 $0 $0
555700 $2,715,433 $39,120 $572,008 $585,151 $208,432 $85,450 $1,111,797 $85,200 $28,275 $0 $0 $0 $0
20 Solar Select Adjustment ($74,108) ($5A18) ($5,500) ($8,078) ($10,881) ($10,919) ($11,858) ($11,480) ($9,974)1/ $0 $0 $0 $0
21 555380 $11,445,635 $1,512,232 $1,370,915 $1,499,825 $1,536,936 $1,516,066 $1,444,087 $1,501,236 $1,064,338 $0 $0 $0 $0
22 Clearwater Adjustment ($11,445,635)/ ($1,512,232) ($1,370,915) ($1,499,825) ($1,536,936) ($1,516,066) ($1,444,087) ($1,501,236) ($"064,338) $0 $0 $0 $0
23 Chelan Adj of LMC vs Contract Price ($3,277,812) $ (3,686) $ (87,076) $ (991,655) $ (814,080) $ (324,448) $ (377,821) $ (453,989) $ (225,057) R-04 _ $ _ $ _ $ _
24 Columbia Basin Adj of LMC vs Contract Price ($2,901,916) $ - $ - $ (532,293) $ (1,134,597) $ (681,394) $ (517,923) $ - $ (35,709) R-05 $ - $ - $
25 Company Absorbed Wind Adjustment ($2,038,376) ($135,963) ($235,489) ($418,244) ($305,473) ($272,299) ($236,388) ($237,714) ($196,806) $0 $0 $0 $0
555710 $876,117 $111,115 $194,678 $88,561 $87,492 $83,461 $99,714 $106,637 $104,459 $0 $0 $0 $0
555740 $4,114,406 $671,321 $741,858 $1.138,769 $110,480 $24,793 $378,850 $512,378 $415,579 $120,378 $0 $0 $0
$140,457,525 $14,649,944 $22,918,792 $17,154,312 $15,506,870 $16,498,614 $17,744,546 $19,209,958 $16,654,111 $120,378 $0 $0 $0
($682,037)
447 SALES FOR RESALE
26 Short-Term Sales ($95,224,839) ($12,168,965) ($13,083,760) ($14,197,853) ($11,728,570) ($9,705,613) ($11,217,958) ($14,122,714) ($8,895,920) ($103,486) $0 $0 $0
27 Nichols Pumping Index Sale ($1,061,259) ($132,824) ($151,283) ($82,969) ($63,712) ($93,333) ($123,074) ($208,636) ($205,428) $0 $0 $0 $0
28 Soverign/Kaiser Load Following $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
29 Pend Oreille DES ($347,348) ($47,098) ($41,677) ($43,507) ($43,870) ($45,562) ($41,049) ($48,770) ($35,815) $0 $0 $0 $0
30 Merchant Ancillary Services ($33,553,113) ($3,467,041) ($4,006,451) ($4,215,854) ($5,077,331) ($4,646,623) ($4,925,362) ($3,557,289) ($3,657,162) $0 $0 $0 $0
31 Total 447 Sales for Resale ($130,186,559) ($15,815,928) ($17,283,171) ($18,540,183) ($16,913,493) ($14,491,131) ($16,307,443) ($17,937,409) ($12,794,325) ($103,486) $0 $0 $0
447 SALES FOR RESALE
447000 ($65,808,328) ($8,042,952) ($10,073,662) ($8,948,674) ($7,610,973) ($8,776,385) ($11,110,798) ($6,735,870) ($4,509,014) $0 $0 $0 $0
32 Deduct Revenue From Solar Select $1,173,812 $64,839 $65,458 $74,296 $106,010 $171,239 $224,635 $256,029 $211,3061/ $0 $0
447100 ($4,945,051) ($620,226) $1,031,D40 ($2,100,093) ($1,681,328) $1,339,548 $3,629,520 ($4,119,218) ($2,424,294) $0 $0 $0 $0
447150 ($17,655,947) ($2,829,559) ($3,357,951) ($1,727,094) ($1,353,212) ($1,884,091) ($2,038,731) ($2,543,716) ($1,921,593) $0 $0 $0 $0
447700 ($3,490,642) ($42,410) ($618,313) ($1,075,555) ($458,793) ($56,009) ($1,115,014) ($91,422) ($33,126) $0 $0 $0 $0
447710 ($876,117) ($111,115) ($194,678) ($88,561) ($87,492) ($83,461) ($99a14) ($106,637) ($104,459) $0 $0 $0 $0
447720 ($33,553,113) ($3,467,041) ($4,006,451) ($4,215,854) ($5,077,331) ($4,646,623) ($4,925,362) ($3,557,289) ($3,657,162) $0 $0 $0 $0
447740 ($5,031,173) ($767,464) ($128,614) ($458,648) ($750,364) ($555,349) ($871,979) ($1,039,286) ($355,983) ($103,486) $0 $0 $0
($130,186,559) ($15,815,928) ($17,283,171) ($18,540,183) ($16,913,483) ($14,491,131) ($16,307,443) ($17,937,409) ($12,794,325) ($103,486) $0 $0 $0
501 FUEL-DOLLARS
33 Kettle Falls Wood-501110 $5,216,733 $933,844 $797,711 $883,284 ($5,108) $0 $678,159 $929,914 $998,929 $0 $0 $0 $0
34 Kettle Falls Gas-501120 ($1,111) $287 $1,741 ($962) ($5,401) ($243) $1,539 ($750) $2,678 $0 $0 $0 $0
35 Colstrip Coal-501140 $21,344,909 $2,521,742 $3,676,147 $2,849,365 $1,696,656 $1,519,144 $1,866,322 $3,612,047 $3,603,486 $0 $0 $0 $0
36 Colstrip Oil-501160 $173,813 $0 $47,196 $20,870 $11,078 $6,512 $22,187 $65,970 $0 $0 $0 $0 $0
37 Total 501 Fuel Expense $26,734,344 $3.455.873 $4.522.795 $3.752.557 $1.697.225 $1.525,413 $2.568.207 $4,607,181 $4,605,093 $0 $0 $0 $0
501 FUEL-TONS
38 Kettle Falls 270,417 47,598 41,680 46,433 - - 35,047 47,759 51,900 - - -
39 Colstrip 585,353 90,120 82,086 78,070 46,696 40,389 51,303 96,920 99,769 - - - -
501 FUEL-COST PER TON
40 Kettle Falls wood $19.62 $19.14 $19.02 $19.35 $19.47 $19 25
41 Colstrip coal $27.98 $44.78 $36.50 $36.33 $37.61 $36.38 $37.27 $36.12
Page 27
2025 WA ID Actual Deferrals.xlsx ID Monthly 2

Q3 2025 ID PICA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO DEFERRED POWER COST CALCULATION-ACTUAL SYSTEM POWER SUPPLY EXPENSES
Line
No. TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25
547 FUEL
42 NE CT Gas-547213 ($3,748) $1,211 $639 ($1,163) ($5,082) ($324) $453 ($907) $1,425 $0 $0 $0 $0
43 Boulder Park-547216 $1,911,754 $90,977 $373,870 $266,081 $158,946 $108,083 $249,552 $306,300 $357,945 $0 $0 $0 $0
44 Kettle Falls CT-547211 $19,918 $3,074 $3,102 $1,817 $10,082 $454 ($636) $1,272 $753 $0 $0 $0 $0
45 Coyote Springs2-547610 $28,831,843 $5,503,409 $4,984,616 $4,197,442 $2,644,029 $1,925,515 $3,360,708 $2,563,637 $3,652,487 $0 $0 $0 $0
46 Lancaster-547312 $23,403,373 $4,823,423 $4,344,662 $3,664,728 $1,295,217 $689,411 $2,794,405 $2,798,290 $2,993,237 $0 $0 $0 $0
47 Rathdrum CT-547310 $17,209,134 $3,373,285 $3,237,724 $2,055,231 $1,298,231 $1,262,137 $1,931,468 $2,124,366 $1,926,692 $0 $0 $0 $0
48 Total 547 Fuel Expense $71,372,274 $13,795,379 $12,944,613 $10,194,136 $5,401,423 $3,985,276 $8,335,950 $7,792,958 $8,932,539 $0 $0 $0 $0
49 TOTAL NET EXPENSE $108,377,584 $16.085.268 $23.103,029 $12,550,822 $5.692.035 $7,518,172 $12,341,260 $13,672,688 $17,397,418 $16,892 $0 $0 $0
202501 0 2025020 202503 202504 202505 j 202506 202507 202508 1 202509 202510 202511 202512
456 TRANSMISSION REVENUE
50 456100 ED AN ($17,578,259) ($2,462,659) ($2,391,307) ($2,394,241) ($2,129,966) ($2,217,910) ($1,957,539) ($2,114,367) ($1,910,270) so $0 $0 $0
51 456120 ED AN-BPA Trans. ($616,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) So $0 $0 $0
52 456020 ED AN-Sale of excess BPA Trans $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
53 456030 ED AN-Clearwater Trans ($1,204,835) ($154,335) ($154,000) ($154,000) ($148,500) ($148,500) ($148,500) ($148,500) ($148,500) $0 $0 $0 $0
54 456130 ED AN-Ancillary Services Revenue ($876,117) ($111,115) ($194,678) ($88,561) ($87,492) ($83,461) ($99,714) ($106,637) ($104,459) $0 $0 $0 $0
55 456017 ED AN-Low Voltage ($80,504) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) $0 $0 $0 $0
56 456700 ED ID-Low Voltage ($41,864) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) $0 $0 $0 $0
57 456705 ED AN-Low Voltage ($1,186,352) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) $0 $0 $0 $0
58 Total 456 Transmission Revenue ($21,583,931) ($2,968,699) ($2,980,575) ($2,877,392) ($2,606,548) ($2,690,461) ($2,446,343) ($2,610,094) ($2,403,819) $0 $0 $0 $0
565 TRANSMISSION EXPENSE
59 565000 ED AN $19,370,712 $2,245,132 $2,246,019 $2,650,847 $2,470,366 $2,393,183 $2,389,631 $2,483,293 $2,492,241 $0 $0 $0 $0
60 565710 ED AN $47,816 $5,977 $5,977 $5,977 $5,977 $5,977 $5,977 $5,977 $5,977 $0 $0 $0 $0
61 Total 565 Transmission Expense $19,418,528 $2,251,109 $2,251,996 $2,656,824 $2,476,343 $2,399,160 $2,395,608 $2,489,270 $2,498,218 $0 $0 $0 $0
557 Expense
62 557165 ED AN CAISO $168,312 $2,984 $4,818 $26,074 $57,166 $69,241 $4,074 $2,102 $1,853 $0 $0 $0 $0
63 557167 ED AN $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
64 557018 ED AN Merchandis $7,429 $4,073 $3,781 ($130) $0 $0 ($295) $0 $0 $0 $0 $0 $0
65 557020 ED AN-Tariff Cost $27,652 $0 $0 $27,652 $0 $0 $0 $0 $0 $0 $0 $0 $0
66 Total 557 ED AN Broker&Related Fees $203,393 $7,057 $8,599 $53,596 $57,166 $69,241 $3,779 $2,102 $1,853 $0 $0 $0 $0
537 Expense
67 537000 ED AN-MT Invasive Species $517,776 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,7221/
68 Total 537 ED AN MT Invasive Species $517,776 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $0 $0 $0 $0
Other Purchases and Sales
69 Econ Dispatch-557010 $10,292,767 $1,480,819 $2,380,180 $3,023,389 $471,998 $333,049 $385,530 $792,414 $1,425,388 $0 $0 $0 $0
70 Econ Dispatch-557150 ($1,663,302) ($1,868,318) ($2,621,649) ($651,285) $1,671,560 $1,762,018 $462,563 $169,122 ($587,313) $0 $0 $0 $0
71 Gas Bookouts-557700 $1,589,403 $468,775 $116,900 $309,405 $140,581 $0 $36,270 $485,019 $32,453 $0 $0 $0 $0
72 Gas Bcokouts-557711 ($1,589,403) ($468,775) ($116,900) ($309,405) ($140,581) $0 ($36,270) ($485,019) ($32,453) $0 $0 $0 $0
73 Intraco Thermal Gas-557730 $6,093,917 $1,155,447 $760,783 $1,030,660 $393,919 $143,763 $206,915 $1,303,214 $1,099,216 $0 $0 $0 $0
74 Fuel Dispatch456010 ($759,611) $224,169 ($56,875) ($357,856) ($469,275) ($99,774) $0 $0 $0 $0 $0 $0 $0
75 Fuel Dispatch456015 ($12,032,861) ($661,280) ($497,104) ($1,903,363) ($1,941,354) ($1,978,461) ($925,962) ($2,864,806) ($1,260,531) $0 $0 $0 $0
76 Other Elec Rev-Extraction Plant Cr-456018 ($376,435) ($42,833) ($50,849) ($44,832) ($55,901) ($40,186) ($44,217) ($48,211) ($49,406) $0 $0 $0 $0
77 Other Else Rev-Specified Source-456019 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
78 Intraco Thermal Gas-456730 ($1,989,694) ($77,453) ($16,045) ($638,673) ($430,223) ($267,373) ($125,954) ($185,745) ($248,228) $0 $0 $0 $0
79 Fuel Bookouls-456711 $718,373 $61,063 $33,576 $172,721 $89,526 $3,817 $732 $352,768 $4,170 $0 $0 $0 $0
80 Fuel Bookouls-456720 ($718,373) ($61,063) ($33,576) ($172,721) ($89,526) ($3,817) ($732) ($352,768) ($4,170) $0 $0 $0 $0
81 Other Purchases and Sales Subtotal ($435,219) $210,551 ($101,559) $458.040 ($359,276) ($146,964) ($41,125) ($834,012) $379,126 $0 $0 $0 $0
82 Misc Revs 456016 ED AN ($103,865) ($900) $0 $44.535 $0 $0 $0 $0 ($147,500) $0 $0 $0 $0
83 REC Revenue Subtotal ($103,865) ($900) $0 $44,535 $0 $0 $0 $0 ($147,500) $0 $0 $0 $0
84 Misc.Power Exp.Actual-557160 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
85 Misc.Power Exp.Subtotal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
86 Wind REC Exp Authorized $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
87 Wind REC Exp Actual 557395 $687 $52 $71 $50 $61 $94 $108 $135 $116 $0 $0 $0 $0
88 Wind REC Subtotal $687 $52 $71 $50 $61 $94 $108 $135 $116 $0
Page 28
2025 WA ID Actual Deferrals.xlsx ID Monthly 3

Q3 2025 ID PICA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO DEFERRED POWER COST CALCULATION-ACTUAL SYSTEM POWER SUPPLY EXPENSES
Line
No. TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25
89 456030 ED ID-Clearwater Trans $119,942 $14,308 $15,434 $15,400 $15,400 $14,850 $14,850 $14,850 $14,850 $0 $0 $0 $0
90 456380-ED-ID-Clearwater REC Revenue ($762,566) ($84,633) ($107,275) ($89,397) ($88,295) ($99,866) ($96,205) ($96,622) ($100,273) $0 $0 $0 $0
91 Clearwater ($642,624) ($70,325) ($91,841) ($73,997) ($72,895) ($85,016) ($81,355) ($81,772) ($85,423) $0 $0 $0 $0
92 Net Resource Optimization ($538,397) $209,703 ($101,488) $502,625 ($359,215) ($146,870) ($41,017) ($833,877) $231,742 $0 $0 $0 $0
93 EIM Incremental O&M Costs(Idaho share) $265,453 $32205 $26428 $25328 $32087 $29628 $39629 0 $34606 $45,542
94 Adjusted Actual Net Expense $106,017,782 $15,611,040 $22,280,870 $12,902,528 $5,283,695 $7,158,576 $12,276,283 $12,737,645 $17,750,253 $16,892
Q 40,987.80 -
0.90 =
©45,542.00 T+
Page 29
2025 WA ID Actual Deferrals.xlsx ID Monthly 4

Q3 2025 ID PCA Quarterly Report
Avista Corp.-Resource Accounting
Idaho Electric Jurisdiction
Power Costs Adjustment (PCA) - Load Change Adjustment - 2025
Retail Revenue Credit excluding
Clearwater-MWh Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25 YTD
Total Billed Sales 312,860 309,308 274,035 255,324 221,646 237,222 257,843 268,504 (29,426) 2,136,742
Deduct Prior Month Unbilled (137,264) (145,445) (132,541) (124,764) (106,829) (119,536) (127,614) (150,599)V (149,750) (1,044,592)
Add Current Month Unbilled 145,445 132,541 124,764 106,829 119,536 127,614 150,599 149,750V 1,057,078
Total Retail Sales 321,041 296,404 266,258 237,389 234,353 245,300 280,828 267,655 J (179,176) 2,149,228
Test Year Consumption 304,450 275,917 276,088 250,222 227,023 225,845 256,211 254,893 218,497 235,421 260,464 297,899 2,070,649
Difference from Test Year 16,591 20,487 (9,830) (12,833) 7,330 19,455 24,617 12,762 (397,673) 78,579
Load Change Adjustment Rate- $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50
$/MWh
Total Load Change Adjustment-$ $406,480 $501,932 ($240,835) ($314,409) $179,585 $476,648 $603,117 R-03'$312,669./ ($9,742,989) $1,925,187
Page 30
Page 4 of 4

Q3 2025 ID PCA Quarterly Report
Electric Revenue Report by Revenue Class Data Source:Financial Reporting
Data Updated Daily
Accounting Period:202508V State Code:ID
Rate Schedule Desc Meter Qty Usage Qty Revenue Amt YTD Meter Qty YTD Usage I YTD Revenue Amt
0001-RESIDENTIAL 0 0 (269,079) 0 0 (2,248,064)
0011-GENERAL SERVICE 0 0 (197,521) 0 0 (1,493,037)
0012-RESID&FARM-GEN SERV 0 0 (6,550) 0 0 (64,749)
0021-LARGE GENERAL SERV 0 0 (16,553) 0 0 (168,343)
0022-RESID&FRM-LGE GEN SE 0 0 (1,480) 0 0 (12,090)
0025-EXTRA LGE GEN SERV 0 0 (70,743) 0 0 (577,887)
0031-PUMPING SERVICE 0 0 (22,279) 0 0 (107,125)
0032-PUMPING SVC RES&FRM 0 0 (2,230) 0 0 (10,303)
0042-CO OWND ST LTS SO VA 0 0 (1,051) 0 0 (8,427)
0044-CST OWND ST LT SO VA 0 0 (49) 0 0 (410)
0045-CUST OWND ST LT ENGY 0 0 (56) 0 0 (451)
0046-CUST OWND ST LT S V 0 0 (186) 0 0 (1,512)
0047-AREA LIGHT-COM&INDUS 0 0 (24) 0 0 (312)
0048-AREA LGHT-FARM&RESID 0 0 (145) 0 0 _ (1,215)
0049-AREA LGHT-HI PRIES SO 0 0 (412) 0 0 _ (3,289)
025 EXTRA LARGE GEN SERVICE/POTLATCH 0 0 (72,075) 0 0 (558,000)
10023-DCFC-ID 0 0 (47) 0 0 (255)
Overall-Summary 0 01 (660,482) 0 (5,255,467)
Page 1 of 3 Run Date: Sep 5,2025
IFor Internal Use Only
0.996223 Settlement Revenue Conversion Factor Changes October 1st w/GRC
(657,988)O
H:\Power Deferrals\Power Deferral Journals\2_ID PCA\2025 ID PCA\Cognos Reports\202508 Revenue_RateSch_CM_YTD for ID PCA.xlsx 9/5,Ng5312:12 PM

Q3 2025 ID PCA Quarterly Report
Revenue By Revenue Classy Data Source: Financial Reporting
Electric v Data Updated Daily
State Code:ID
Accounting Period Service I Revenue Class Revenue Class Desc Meter Qty Usage Qty Revenue Amt I YTD Average Meters YTD Usage YTD Revenue Amt
202508ve ED 01 01 RESIDENTIAL 129,113 113,118,166 13,066,445 128,832 947,968,081 108,649,322
21 21 FIRM COMMERCIAL 19,246 95,036,994 8,582,421 19,269 705,798,394 63,988,203
31 31 FIRM-INDUSTRIAL 307 100,472,271 5,112,208 316 798,576,623 40,473,822
39 39 FIRM-PUMPING-IRRIGATION ONLY 39 623,926 62,794 39 2649492 272,969
51 51 LIGHTING-PUBLIC STREET AND HIWAY 203 555,127 261,563 203� 4:518:026 2,091,518
80 80 INTERDEPARTMENT REVENUE 51 202,024 19,432 53 1,750,406 160,879
83 83 MISC-SERVICE REVENUE SNP 0 0 9,168 0 0 74,572
85 85 MISC-RENT FROM ELECTRIC PROPERTY 0 0 9,548 0 0 76,381
OD OD Other Electric Direct 0 0 1,500 0 0 8,400
RP RP Rent Permits 0 0 0 0 0 1,735
ED-Summary 148,959 310,008,509 27,125,079 148,712 2,461,261,022 215,797,800
202508-Summary 148,959 310,008,509 27,125,079 148,712 2,461,261,022 215,797,800
Overall-Summary 148,959 310,008,509 V 27,125,079 148,712 2,461,261,022 215,797,800
Page 2 of 4 Run Date: Sep 5,2025
Total Billed Sales-input tab,deferral calc workbook
IFor Internal Use Only I
H:\Power Deferrals\Power Deferral 3ournals\2_ID PCA\2025 ID PCA\Cognos Reports\202508 Revenue By Revenue Class ID.xlsx 9/5/26 IN:45 PM

Q3 2025 ID PCA Quarterly Report
Current Month Journal Entry
Jurisdiction: ID o
Revenue Class Revenue Class Desc Town Code Revenue Class Rate Schedule Gross Unbilled kWh Total Unbilled+Basic Charge
3800 01 001 50,014,500 $5,583,249
3800 01 011 0
3800 01 012 1,217,616 $158,508
01 01 RESIDENTIAL 3800 01 022 275,118 $22,310
3800 01 032 187,856 $24,797
3800 21 011 35,473,410 $3,085,548
3800 21 021 2,138,947 $151,474
3800 21 025 5,816,187 $343,130
21 21 FIRM COMMERCIAL 3800 21 031 3,273,295 $341,920
3800 31 011 1,184,544 $98,864
31 FIRM-INDUSTRIAL 3800 31 021 937,799 $66,118
3800 31 025 24,131,223 $1,449,962
3800 31 031 773,271 $80,707
31 31 FIRM INDUSTRIAL 3800 31 025P 24,326,445 $1,319,067
31 FIRM-INDUSTRIAL 3800 31 025PG 29,426,000 $1,064,338
i
21 -Summary $3,922,072
31 -Summary $4,079,057
ID-Summary 179,176,209
Unbilled"'input tab, deferral calc workbook
P 33
G:\CLOSE\202508\Revenue\REVUNBL\REVUNBLD - E\SOX Electric Un II led (2).xlsx

Q3 2025 ID PCA Quarterly Report
Columbia Basin Hydro Customer Cost Calculations - August 2025
Generation Mid-C Valuation Contract Valuation
Off Mid-C On Mid-C Off Mid-C Busbar
On Peak Peak Total Peak Peak Weighted Total Cost Cumul.Total Price Total Cost Cumul.Total Customer Cost
Date (MWh) (MWh) (MWh) ($/MWh) ($/MWh) ($/MWh) ($000s) Cost($000s) ($/MWh) Daily Delivery($) ($000s) Cost($000s) ($000s)
8/1/2025 1,773 610 2,383 38.27 33.78 37.12 88,457 88,457 43.17 8,116 110,990 110,990 88,457
8/2/2025 1,608 570 2,178 38.27 33.78 37.09 80,791 169,248 43.17 8,116 102,140 213,130 169,248
8/3/2025 1,669 526 2,195 27.45 27.45 27.45 60,253 229,500 43.17 8,116 102,874 316,004 229,500
8/4/2025 1,706 572 2,278 34.14 27.45 32.46 73,950 303,450 43.17 8,116 106,457 422,461 303,450
8/5/2025 1,682 565 2,247 37.04 34.73 36.46 81,926 385,376 43.17 8,116 105,119 527,580 385,376
8/6/2025 1,673 552 2,225 32.51 31.23 32.19 71,628 457,004 43.17 8,116 104,169 631,749 457,004
8/7/2025 1,294 559 1,853 33.69 32.65 33.38 61,846 518,850 43.17 8,116 88,110 719,859 518,850
8/8/2025 970 327 1,297 35.73 35.21 35.60 46,167 565,018 43.17 8,116 64,107 783,967 565,018
8/9/2025 945 320 1,265 35.73 35.21 35.60 45,028 610,045 43.17 8,116 62,726 846,693 610,045
8/10/2025 959 317 1,276 44.94 44.94 44.94 57,343 667,389 43.17 8,116 63,201 909,893 667,389
8/11/2025 986 326 1,312 60.09 44.94 56.32 73,896 741,285 43.17 8,116 64,755 974,648 741,285
8/12/2025 967 323 1,290 61.46 50.52 58.72 75,752 817,037 43.17 8,116 63,805 1,038,454 817,037
8/13/2025 1,311 322 1,633 36.65 33.55 36.04 58,854 875,891 43.17 8,116 78,613 1,117,066 875,891
8/14/2025 1,750 581 2,331 35.13 33.46 34.71 80,920 956,811 43.17 8,116 108,745 1,225,811 956,811
8/15/2025 1,668 576 2,244 35.47 34.56 35.23 79,065 1,035,876 43.17 8,116 104,989 1,330,801 1,035,876
8/16/2025 1,527 531 2,058 35.47 34.56 35.23 72,509 1,108,385 43.17 8,116 96,960 1,427,760 1,108,385
8/17/2025 1,498 506 2,004 28.66 28.66 28.66 57,435 1,165,819 43.17 8,116 94,629 1,522,389 1,165,819
8/18/2025 1,573 509 2,082 37.86 28.66 35.61 74,142 1,239,961 43.17 8,116 97,996 1,620,385 1,239,961
8/19/2025 1,599 526 2,125 42.42 36.04 40.84 86,790 1,326,751 43.17 8,116 99,852 1,720,237 1,326,751
8/20/2025 1,633 540 2,173 48.59 35.64 45.37 98,595 1,425,346 43.17 8,116 101,924 1,822,161 1,425,346
8/21/2025 1,669 558 2,227 64.00 44.32 59.07 131,547 1,556,893 43.17 8,116 104,255 1,926,417 1,556,893
8/22/2025 1,679 556 2,235 74.27 53.91 69.20 154,666 1,711,558 43.17 8,116 104,601 2,031,017 1,711,558
8/23/2025 1,615 551 2,166 74.27 53.91 69.09 149,643 1,861,202 43.17 8,116 101,622 2,132,640 1,861,202
8/24/2025 1,616 532 2,148 90.07 90.07 90.07 193,470 2,054,672 43.17 8,116 100,845 2,233,485 2,054,672
8/25/2025 1,655 552 2,207 114.59 90.07 108.45 239,358 2,294,030 43.17 8,116 103,392 2,336,877 2,294,030
8/26/2025 1,627 542 2,169 76.21 50.05 69.67 151,121 2,445,151 43.17 8,116 101,752 2,438,628 2,438,628
8/27/2025 1,575 533 2,108 47.11 37.79 44.75 94,333 2,539,484 43.17 8,116 99,118 2,537,747 2,537,747
8/28/2025 1,514 517 2,031 50.09 41.33 47.86 97,211 2,636,694 43.17 8,116 95,794 2,633,541 2,633,541
8/29/2025 1,427 493 1,920 50.09 41.33 47.84 91,860 2,728,555 43.17 8,116 91,002 2,724,543 2,724,543
8/30/2025 1,344 446 1,790 42.66 33.15 40.29 72,121 2,800,676 43.17 8,116 85,390 2,809,933 2,800,676
8/31/20251 1,381 1 449 1,830 1 33.15 1 33.15 1 33.15 60,665 2,861,341 43.17 8,116 87,117 2,897,050 2,861,341
61,280
Actual Cost 2,897,050
Allowed 2,861,341
Adjustment 35,709 R-os'
H:\Power Deferrals\Power Deferral Journals\2_ID PCA\2025 ID PCA\2025 CBH and Chelan Generation Reports\08)Aug\202508 CBH and Chelan Contract vs Market(PCA)with transmissionq,%Q lsx

Q3 2025 ID PCA Quarterly Report
Chelan Hydro Customer Cost Calculations - August 2025
Generation Mid-C Valuation Contract Valuation
Total Diff
[Positive-
On Off Mid-C On Mid-C Off Mid-C Busbar Total Contract
Peak Peak Total Peak Peak Weighted Total Cost Cumul.Total Price Cost Cumul.Total Customer higher than
Date (MWh) (MWh) (MWh) ($/MWh) ($/MWh) ($/MWh) ($000s) Cost($000s) ($/MWh) ($000s) Cost($000s) Cost($000s) Market]
8/1/2025 447 258 705 38.83 33.78 36.98 26,055 26,055 54.02 38,056 38,056 26,055 12,001
8/2/2025 558 190 748 38.83 33.78 37.55 28,068 54,124 54.02 40,379 78,436 54,124 12,311
8/3/2025 - 733 733 27.45 27.45 20,121 74,245 54.02 39,596 118,031 74,245 19,475
8/4/2025 514 237 751 34.98 27.45 32.60 24,485 98,730 54.02 40,568 158,600 98,730 16,083
8/5/2025 638 379 1,016 37.33 34.73 36.36 36,943 135,673 54.02 54,883 213,483 135,673 17,940
8/6/2025 744 356 1,100 32.67 31.23 32.20 35,409 171,082 54.02 59,394 272,877 171,082 23,985
8/7/2025 746 447 1,193 33.82 32.65 33.38 39,807 210,889 54.02 64,418 337,295 210,889 24,610
8/8/2025 917 448 1,364 35.79 35.21 35.60 48,558 259,447 54.02 73,682 410,976 259,447 25,124
8/9/2025 813 423 1,236 35.79 35.21 35.59 43,973 303,421 54.02 66,740 477,717 303,421 22,767
8/10/2025 - 1,138 1,138 44.94 44.94 51,142 354,563 54.02 61,474 539,191 354,563 10,332
8/11/2025 880 302 1,182 61.98 44.94 57.63 68,114 422,677 54.02 63,850 603,041 422,677 (4,264)
8/12/2025 931 384 1,315 62.83 50.52 59.23 77,863 500,540 54.02 71,008 674,049 500,540 (6,855)
8/13/2025 703 349 1,051 37.04 33.55 35.88 37,713 538,253 54.02 56,774 730,823 538,253 19,061
8/14/2025 741 314 1,055 35.34 33.46 34.78 36,677 574,929 54.02 56,963 787,786 574,929 20,286
8/15/2025 761 338 1,098 35.58 34.56 35.27 38,723 613,652 54.02 59,313 847,099 613,652 20,590
8/16/2025 687 470 1,157 35.58 34.56 35.17 40,669 654,321 54.02 62,473 909,572 654,321 21,804
8/17/2025 - 1,128 1,128 28.66 28.66 32,328 686,649 54.02 60,933 970,505 686,649 28,605
8/18/2025 642 175 817 39.01 28.66 36.79 30,060 716,709 54.02 44,134 1,014,639 716,709 14,074
8/19/2025 722 347 1,068 43.22 36.04 40.89 43,671 760,380 54.02 57,692 1,072,331 760,380 14,021
8/20/2025 629 294 923 50.21 35.64 45.57 42,035 802,415 54.02 49,833 1,122,163 802,415 7,797
8/21/2025 709 353 1,062 66.46 44.32 59.10 62,765 865,180 54.02 57,368 1,179,532 865,180 (5,397)
8/22/2025 617 389 1,006 76.81 53.91 67.95 68,324 933,505 54.02 54,316 1,233,848 933,505 (14,008)
8/23/2025 755 465 1,219 76.81 53.91 68.08 82,994 1,016,499 54.02 65,849 1,299,697 1,016,499 (17,145)
8/24/2025 - 956 956 90.07 90.07 86,107 1,102,606 54.02 51,642 1,351,339 1,102,606 (34,465)
8/25/2025 824 403 1,226 117.65 90.07 108.60 133,138 1,235,744 54.02 66,227 1,417,566 1,235,744 (66,911)
8/26/2025 809 391 1,200 79.48 50.05 69.89 83,869 1,319,613 54.02 64,823 1,482,389 1,319,613 (19,046)
8/27/2025 797 372 1,169 48.27 37.79 44.94 52,510 1,372,123 54.02 63,121 1,545,510 1,372,123 10,611
8/28/2025 760 374 1,134 51.19 41.33 47.94 54,341 1,426,464 54.02 61,231 1,606,741 1,426,464 6,889
8/29/2025 866 326 1,192 51.19 41.33 48.49 57,779 1,484,243 54.02 64,364 1,671,104 1,484,243 6,585
8/30/2025 747 369 1,115 43.85 33.15 40.31 44,950 1,529,193 54.02 60,231 1,731,336 1,529,193 15,281
8/31/2025 - 1,098 1,098 33.15 33.15 36,399 1,565,591 54.02 59,313 1,790,648 V 1,565,591'/ 22,914
33,149 225,057
Actual Cost 11790,648
Allowed 1,565,591
Adjustment 225,057 a- 1
H:\Power Deferrals\Power Deferral Journals\2_ID PCA\2025 ID PCA\2025 CBH and Chelan Generation Reports\08)Aug\202508 CBH and Chelan Contract vs Market(PCA)with transmission costs.xlpxage 35

Q3 2025 ID PCA Quarterly Report
Avista Corporation Journal Entry Printed 09/03/2025 at 10:05 AM
Journal: 240-EIM DEFERRAL Effective Date: 202508
Team: Energy Delivery Accounting Last Saved by: Ian Williams Last Update:09/03/2025 10:04 AM
Type: C Submitted by: Ian Williams Approval Requested:09/03/2025 10:05 AM
Category: DJ Approved by:
Currency: USD
Seq. Co. FERC Ser. Jur. S.I. Debit Credit Comment
10 001 431230-INTEREST ON REG DEFERRALS-ST ED WA DL 1,733.86 0.00 Provisional EIM WA-202508 Interest
20 001 229030-ACCUM PROV RATE REFUND-EIM ED WA DL 17,067.62 0.00 Provisional EIM WA-202508 Deferral
CAP
30 001 184057-CLEARING ACCT-ENERGY DLIVERY ZZ ZZ DL 0.00 18,801.48 Provisional EIM WA-202508 Deferral
ACCT
Totals: 18,801.48 18,801.48
Seq. Project Task Exp. Org Quantity Co. FERC Ser. Jur.
10 03805834-EIM Deferral-ID 182334-Regulatory Asset-EIM 885 D57- (29,129.92) 001 184057-CLEARING ACCT-ENERGY ZZ ZZ
Miscellaneous Misc DLIVERY ACCT
Comment:EIM Deferral ID-202508 Amortization
20 03805834-EIM Deferral-ID 407334-Amort of EIM Defer 885 D57- 29,129.92 001 184057-CLEARING ACCT-ENERGY ZZ ZZ
Miscellaneous Misc DLIVERY ACCT
Comment:EIM Deferral ID-202508 Amortization
30 03805834-EIM Deferral-ID 407434-EIM Deferred O&M 885 D57- 0(40,987.80),/001 182386-REGULATORY ASSET ID ED ID
Miscellaneous Misc PCA DEFERRAL 2
Comment:EIM PCA Deferral ID-202508
40 02807414-EIM Interest Deferral-WA 407439-Amort EIM Defferal 885 D57- (18,801.48) 001 184057-CLEARING ACCT-ENERGY ZZ ZZ
Miscellaneous Misc DLIVERY ACCT
Comment:Provisional EIM WA-202508 Amortization
Total: (59,789.28)
Explanation:
To record EIM Deferred costs in accordance with IPUC Order No.34606-
Post costs of which 90%are to be deferred through the PCA.
Page 1 of 2
Page 36

Q3 2025 ID PCA Quarterly Report
AVISTA UTILITIES
POWER COST ADJUSTMENT REPORT
THIRD QUARTER 2025
MONTH OF SEPTEMBER
Page 37

Q3 2025 ID PCA Quarterly Report
Avista Corporation Journal Entry Printed 10/07/2025 at 3:01 PM
Journal: 480-ID PCA Effective Date: 202509 0
Team: Resource Accounting Last Saved by: Cheryl Kettner Last Update: 10/07/2025 2:59 PM
Type: C Submitted by: Cheryl Kettner Approval Requested: 10/07/2025 3:01 PM
Category: DJ Approved by:
Currency: USD
October 07, 2025
Prepared by Cheryl Kettner Date
r�ty TaysohJ 10/7/25
Reviewed by Date
Approved for Entry Date
Corporate Accounting use Only
Page 2 of 2
Page 38

Q3 2025 ID PCA Quarterly Report
Avista Corporation Journal Entry Printed 10/07/2025 at 3:01 PM
Journal: 480-ID PCA Effective Date: 202509
Team: Resource Accounting Last Saved by: Cheryl Kettner Last Update: 10/07/2025 2:59 PM
Type: C Submitted by: Cheryl Kettner Approval Requested: 10/07/2025 3:01 PM
Category: DJ Approved by:
Currency: USD
Seq. Co. FERC Ser. Jur. S.I. Debit Credit Comment
5 001 557380-IDAHO PCA-DEF ED ID DL 0.00 626,961.00 rCurrent Deferral Expense-PCA
10 001 182386-REGULATORY ASSET ID PCA ED ID DL 626,961.00 0 0.00 Current Deferral Reg Asset-PCA
DEFERRAL
20 001 182386-REGULATORY ASSET ID PCA ED ID DL 0.00 3,703.00,Interest Expense-PCA
DEFERRAL
30 001 431600-INTEREST EXPENSE ENERGY ED ID DL 3,703.00 0.00 Interest Exp on 182386
DEFERRALS
60 001 182385-REGULATORY ASSET ID PCA ED ID DL 0.00 33,251.00Pending Deferral Interest Exp 182385
DEFERRALI
70 001 431600-INTEREST EXPENSE ENERGY ED ID DL 33,251.00 0.00 Pending Deferral Interest Exp 182385
DEFERRALS
75 001 182387-REGULATORY ASSET ID PCA ED ID DL 645,771.00 0.00 Amortizing Deferral 182387
DEFERRAL
76 001 557390-IDAHO PCA AMT ED ID DL 0.00 645,771.00 Amortizing Deferral 182387
79 001 431600-INTEREST EXPENSE ENERGY ED ID DL 8,851.00 0 0.00 Amortizing Interest Expense 182387
DEFERRALS
80 001 182387-REGULATORY ASSET ID PCA ED ID DL 0.00 8,851.00 vlAmortizing Interest Expense
DEFERRAL
Totals: 1,318,537.00 1,318,537.00
Explanation:
Record deferral of power costs in Idaho,amortization of existing balance,and
interest&DFTT entries.
Page I of 2
Page 39

Q3 2025 ID PCA Quarterly Report
Idaho Power Cost Adjustment(PCA)Deferral Balance-Current Year Bucket
Interest compounds and is calculated monthly
Interest Rate
2024 0.41667%
2025 0.416679/6
Balance Deferral- Interest
Month Ending Account Be .Balance Transfer Surd Reb. Ad'ustments Interest Ad'ustments Balance with Interest GLW Balance Recon Adjustment Notes
12/31/2024 182385 (7,714,835)
1/31/2025 182385 7,714,835 1,447,025 28,985 32,145 9,165,020 9,165,020 DJ240 EIM Deferral
2/28/2025 182385 9,165,020 1,165,452 23,785 38,188 8,013,971 8,013,971 DJ240 EIM Deferral
3/31/2025 182385 8,013,971 197,621 22,795 33,392 8,222,189 8,222,189 DJ240 EIM Deferral
4/30/2025 182385 8,222,189 1,072,522 28,878 34,259 9,300,092 9,300,091 1 DJ240 EIM Deferral
5/31/2025 182385 9,300,092 204,530 26,665 38,751 9,516,707 9,5161707 DJ240 EIM Deferral
6/30/2025 182385 (9,516,707) 1,606,715 35,666 (39,653) (7,913,979) (7,913,979) DJ240 EIM Deferral
This account moves to the Pendin tab
6/30/2025 182386 This account moves from the Pending tab
7/31/2025 182386 1,132,826 2,956,729 0 1,823,903 1,823,903 WA 1-937&CETA Compliance&EIM Deferral
8/31/2025 182386 (1,823,903.00 901,894 40,988 7,600 888,621.00 888,621 0 DJ240 EIM Deferral
9/30/2025 182386 888,621 ✓ R-o1 626,961 12,788 ✓ 3,703 ✓ 278,151 901,409 623,258 DJ240 EIM Deferral
10/31/2025 182386
11/30/2025 182386
12/31/2025 182386
626,961 (3,703)
Entry:
Debit Credit
557380 ED ID 626,961✓Idaho PCA-Def
182386 ED ID 626,961✓ Regulatory Asset ID PCA Deferral
431600 ED ID 3,703✓ Interest Expense Energy Deferrals
182386 ED ID 3,703 vRegulatory Asset ID PCA Deferral
Page 40
H:\Power Deferrals\Power Deferral Joumals\2 ID PCA\2025 ID PCA\2025 DJ480 ID PCA.xlsx

Q3 2025 ID PCA Quarterly Report
Idaho Power Cost Adjustment(PCA)Deferral Balance-Pending Bucket
Interest compounds and is calculated monthly
Interest Rate
20241 0.41667%
20251 0.41667%
Balance Interest Balance with
Month Ending Account Beg.Balance Transfer Activity Adjustments Interest Adjustments Interest GLW Balance Recon Adjustment Notes
12/31/2024 182386
1/31/2025 182386
2/28/2025 182386
3/31/2025 182386
4/30/20251 182386
5/31/20251 182386
6/30/20251 182386
This account moves to the Current Year tab
6/30/2025 182385 This account moves from the Current Year tab (7,913,979)
7/31/2025 182385 7,913,979 (32,975) 7,946,954) 7,946,954 -
8/31/2025 182385 (7,946,954) (33,113) (7,980,067) (7,980,067) 0
9/30/2025 182385 7,980,067 r (33,251) r 8,013,318 7,980,067 33,251
10/31/2025 182385
This account moves to the Amortizing tab
10/31/2025 182387 This account moves from the Amortizing tab
11/30/2025 182387
12/31/2025 182387
(33,251)
Entry:
Debit Credit
431600 ED ID 33,251r Interest Exp Energy Deferrals
182385 ED ID 33,251 ,Regulatory Asset ID PCA Deferral
H:\Power Deferrals\Power Deferral Journals\2 ID PCA\2025 ID PCA\2025 DJ480 ID PCA.xlsx Page 41

Q3 2025 ID PCA Quarterly Report
Idaho Power Cost Adjustment(PCA)Deferral Balance-Amortizing Bucket
Interest compounds and is calculated monthly
Interest Rate
20241 0.41667%
20251 0.41667%
Balance Interest Balance with
Month Ending Account Beg. Balance Transfer Amortization Adjustments Interest Adjustments Interest GLW Balance Recon Adjustment Notes
12/31/2024 182387 (7,197,201)
1/31/2025 182387 (7,197,201) 766,605 (29,988.58) (6,460,585) (6,460,585)
2/28/2025 182387 6,460,585 757,753 26,919.32 5,729,751 5,729,751
3/31/2025 182387 (5,729,751) 671,679 (23,874.15) (5,081,946) (5,081,946)
4/30/2025 182387 5,081,946 625,760 21,174.94 4,477,361 4,477,361
5/31/2025 182387 (4,477,361) 542,748 (18,655.82) (3,953,269) (3,953,269)
6/30/2025 182387 3,953,269 581,283 16,472.09 3,388,458 3,388,458
7/31/2025 182387 (3,388,458) 631,802 (14,119) (2,770,775) (2,770,775)
8/31/2025 182387 2,770,775 657,988 11,545 2,124,332 2,124,332
9/30/2025 182387 (2,124,332) R-021 645,771 (8,851) (1,487,412) (2,124,332)LL(636,920)
10/31/2025 182387
This account moves to the Pending tab
10131/20251 182385 This account moves from the Pending tab
11/30/20251 1823851 1 0
12/31/20251 182385
645,771
Entry:
Debit Credit
182387 ED ID 645,771 r Regulatory Asset ID PCA Deferral
557390 ED ID 645,771 oldaho PCA Amt
431600 ED ID 8,851 o Interest Expense Energy Deferrals
182387 ED ID 8,851 vRegulatory Asset ID PCA Deferral
H:\Power Deferrals\Power Deferral Journals\2 ID PCA\2025 ID PCA\2025 DJ480 ID PCA.xlsx Page 42

Q3 2025 ID PICA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO POWER COST DEFERRALS
Line
No. IDAHO ACTUALS TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25
1 555 Purchased Power $158,288,828 $14,649,944 $22,918,792 $17,154,312 $15,506,870 $16,498,614 $17,744,546 $19,209,958 $16,654,111 $18,286,103 ($50,422) ($142,000) ($142,000)
2 447 Sale for Resale ($145,855,149) ($15,815,928) ($17,283,171) ($18,540,183) ($16,913,483) ($14,491,131) ($16,307,443) ($17,937,409) ($12,794,325 ( 15,668,130). ( 103,946) 0 0
3 501 Thermal Fuel $30,012,075 $3,455,873 $4,522,795 $3,752,557 $1,697,225 $1,525,413 $2,568,207 $4,607,181 $4,605,093 $3,277,731 $0 $0 $0
4 547 CT Fuel $79,901,938 $13,795,379 $12,944,613 $10,184,136 $5,401,423 $3,985,276 $8,335,950 $7,792,958 $8,932,539 $8,529,664 $0 $0 $0
5 456 Transmission Rev ($24,055,141) ($2,968,699) ($2,980,575) ($2,877,392) ($2,606,548) ($2,690,461) ($2,446,343) ($2,610,094) ($2,403,819 (2,471,210) 0 0 0
6 565 Transmission Exp $21,850,094 $2,251,109 $2,251,996 $2,656,824 $2,476,343 $2,399,160 $2,395,608 $2,489,270 $2,498,218 $2,431,566 $0 $0 $0
7 537 MT Invasive Species Exp $582,498 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $0 $0 $0
8 557 Expenses $206,051 $7,057 $8,599 $53,596 $57,166 $69,241 $3,779 $2,102 $1,853 $2,658 $0 $0 $0
9 Adjusted Actual Net Expense $121,369,562 $15,439,457 $22,447,771 $12,448,572 $5,683,718 $7,360,834 $12,359,026 $13,618,688 $17,558,392 $14,453,104 V ($154,368) ($142,000) ($142,000)
AUTHORIZED NET EXPENSE-SYSTEM YTD Jan/25 Feb/25 Mar/25 Apr/25 May/25 J9n/25 Jul/25 Aug/25 Sep/25 Oct/25 Nov/25 Dec/25
10 555 Purchased Power $ 63,137,708 7,435,932 7,069,211 7,433,801 5,672,869 5,579,483 5,419,545 5,937,659 5,836,088 12,753,120 13,316,871 11,607,682 12,096,106
11 447 Sale for Resale $ (54,381,348) (2,316,991) (1,936,564) (2,540,468) (4,230,873) (3,489,856) (5,862,698) (9,557,120) (4,493,194) (19,953,584) (15,137,594) (18,382,654) (26,178,834)
12 501 Thermal Fuel $ 24,160,861 3,151,777 2,749,966 2,896,333 2,060,445 1,526,412 1,782,225 2,879,162 3,146,005 3,968,536 3,155,810 3,272,978 3,539,225
13 547 CT Fuel $ 54,436,101 8,942,104 7,474,530 5,068,911 4,095,763 2,284,385 3,117,887 6,693,265 7,977,571 8,781,685 7,732,236 10,506,214 13,732,592
14 456 Transmission Revenue $ (19,060,360) (1,634,727) (1,811,669) (1,891,560) (1,715,927) (2,123,305) (2,306,697) (2,267,860) (2,209,469) (3,099,146) (3,125,305) (2,986,534) (3,189,458)
15 565 Transmission Expense $ 14,262,704 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 1,439,897 2,743,528 2,743,528 2,743,528 2,743,528
16 90%Palouse Wind and Rattlesnake Flats $ 19,542,000 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 2,442,750 - - - -
17 Remove Columbia Basin Hydro Transmission Project$ (671,336) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) (83,917) - - - -
18 Gas Liquids Revenue/Acct 456 Other Rev Sep-Dec $ (3,537,545) (633,351) (664,038) (880,329) (385,474) (657,028) (615,703) (524,310) (514,471) 1,337,159 1,088,750 1,265,257 2,162,511
19 Montana Invasive Species Expense $ 1,138,336 134,167 134,167 134,167 134,167 134,167 134,167 134,167 134,167 65,000 65,000 65,000 65,000
20 Settlement Adjustments/Other Exp 557 Sep-Dec $ 500,960 52,636 52,636 52,636 52,636 52,636 52,636 52,636 52,636 79,872 79,872 79,872 79,872
21 Shaping Adjustment $ 3,839,288 3,839,288 4,121,443 5,998,200 9,178,058
22 Authorized Net Expense $103,367,369 18,930,277 16,866,969 14,072,221 9,482,336 7,105,624 5,520,092 7,146,329 13,728,063 10,515,458 14,040,611 14,169,543 V 14,228,600
23 Actual-Authorized Net Expense $18,002,193 ($3,490,820) $5,580,802 ($1,623,649) ($3,798,618) $255,210 $6,838,934 $6,472,359 $3,830,329 $3,937,646 V($14,194,979) ($14,311,543) ($14,370,600)
24 Resource Optimization ($782,691) $209,703 ($101,488) $502,625 ($359,215) ($146,870) ($41,017) ($833,877) $231,742 ($244,294) ♦ $0 $0 $0
25 Adjusted Actual-Authorized Net Expense $17,219.502 ($3,281,117) $5,479,314 ($1,121,024) ($4,157,833) $108,340 $6,797,917 $5,638,482 $4,062,071 $3,693,352 v,($14,194,979) ($14,311,543) ($14,370,600)
26 Idaho Allocation 34.47% 34.47% 34.47% 34.47% 34.47% 34.47% 34.47% 34.47% 35.52%wl 35.52%V 35.52%V 35.52%
27 Idaho Share $5,974,344 ($1,131,001) $1,888,720 ($386,417) ($1,433,205) $37,345 $2,343,242 $1,943,585 $1,400,196 $1,311,879 V ($5,042,057) ($5,083,460) ($5,104,437)
28 Idaho 100%Activity(Clearwater) ($692,380) ($70,325 (91,841) (73,997) (72,895) (85,016) (81,355) (81,772) (85,423) (49,756)V 0 0 0
ID Load Change Adjustment(+)Surcharge;(-) ($2 480 687
29 Rebate ) ($406,480) ($501,932) $240,835 $314,409 ($179,585) ($476,648) ($603,117) ($312,669) R-03 ($565,500)V $179,892 $0 $0
30 Net Power Cost Increase(+)Surcharge;(-) $2,791,277
Rebate (E1,607,806) $1,294,947 (E219,579) ($1,191,691) ($227,256) E1,785,239 $1,256,696 $1,002,104 $696,623 V ($4,862,165) (E5,083,460) ($5,104,437)
R-01�
31
90%of Net Power Cost Change $2,512,150 ($1,447,025) $1,165,452 ($197,621) ($1,072,522) ($204,530) $1,606,715 E1,132,826 $901,894 $626,961 1/ (E4,375,949) ($4,575,114) ($4,593,993)
32 Acct 557380 Entry;(+)Rebate,(-)Surcharge ($2,512,150) $1,447,025 ($1,165,452) $197,621 $1,072,522 $204,530 ($1,606,715) ($1,132,826 (901,894) (626,961) $4,375,949 $4,575,114 $4,593,993
33 Energy Imbalance Market Incremental O&M Costs $251,244 $32,205 $26,428 $25,328 $32,087 $29,628 $39,629 $34,606 $45,542 ($14,209) $0 $0 $0
34 90%of Energy Imbalance Market $226,119 $28,985 $23,785 $22,795 $28,878 $26,665 $35,666 $31,145 $40,988 ($12,788) $0 $0 $0
35 Acct 407434 Entry;(+)Rebate,(-)Surcharge ($226,119) ($28,985) ($23,785) ($22,795) ($28,878) ($26,665) ($35,666) ($31,145) ($40,988) $12,788 $0 $0 $0
36 Total Deferral Balance Sheet Entry ($2,738,269) ($1,418,040) $1,189,237 ($174,826) ($1,043,644) ($177,865) $1,642,381 $1,163,971 $942,882 $614,173 ($4,375,949) ($4,575,114) ($4,593,993)
Page 44.1 of 4
2025 WA ID Actual Deferrals.xlsx-10/7/2025

Q3 2025 ID PICA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO DEFERRED POWER COST CALCULATION-ACTUAL SYSTEM POWER SUPPLY EXPENSES
Line
No. TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25
555 PURCHASED POWER
1 Other Short-Term Purchases $25,862,567 $2,347,807 $9,949,684 $1,726,673 ($17,697) $543,667 $2,077,148 $3,227,094 $1,751,972 $4,590,641 ($50,422) ($142,000) ($142,000)
2 Chat County PUD(not in settlement) $12,546,729 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $1,394,081 $0 $0 $0
3 Chelan County PUD(in settlement) $16,115,832 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $1,790,648 $0 $0 $0
4 Douglas County PUD(Wells Settlement) $523,156 $37,007 $27,060 $36,071 $51,732 $55,201 $51,782 $111,264 $121,983 $31,056 $0 $0 $0
5 Douglas County PUD(Wells) $849,501 $94,389 $94,389 $94,389 $94,389 $94,389 $94,389 $94,389 $94,389 $94,389 $0 $0 $0
6 Grant County PUD(Priest Rapids/Wanapum) $25,370,734 $2,817,090 $2,817,090 $2,817,090 $2,834,014 $2,817,090 $2,817,090 $2,817,090 $2,817,090 $2,817,090 $0 $0 $0
7 Bonneville Power Admin.(WNP-3)' 573-Enter $0
8 Inland Power&Light-Deer Lake $7,560 $929 $1,062 $1,156 $767 $740 $776 $686 $808 $636 $0 $0 $0
9 Small Power $809,414 $91,551 $67,808 $128,480 $143,116 $121,014 $104,932 $82,084 $33,885 $36,544 $0 $0 $0
10 Clearwater Wind III,LLC $8,253,449 $1,327,691 $986,871 $1,071,271 $901,880 $1,055,322 $773,983 $734,198 $733,653 $668,580 $0 $0 $0
11 City of Spokane-Upriver $1,684,265 $322,436 $129,608 $422,448 $356,808 $358,390 $94,575 $0 $0 $0 $0 $0 $0
12 City of Spokane-Waste-to-Energy $4,945,555 $684,124 $619,347 $518,361 $477,857 $335,476 $500,920 $631,303 $595,593 $582,574 $0 $0 $0
13 East,South,Quincy Columbia Basin Irrigation Dist $16,841,049 $0 $0 $484,065 $2,269,922 $3,061,573 $3,077,978 $3,271,725 $2,705,680 $1,970,106 $0 $0 $0
14 Rathdrum Power,LLC(Lancaster PPA) $20,738,933 $2,164,734 $2,373,653 $2,327,189 $2,085,304 $1,964,612 $2,457,245 $2,429,571 $2,479,067 $2,457,558 $0 $0 $0
15 Palouse Wind $14,016,880 $969,296 $1,601,821 $2,697,346 $1,914,119 $1,684,273 $1,459,184 $1,517,921 $1,119,861 $1,053,059 $0 $0 $0
16 Rattlesnake Flat,LLC $8,014,154 $390,336 $753,072 $1,485,098 $1,140,611 $1,038,716 $904,696 $859,218 $848,203 $594,204 $0 $0 $0
17 WPM Ancillary Services $979,305 $111,115 $194,678 $88,561 $87,492 $83,461 $99,714 $106,637 $104,459 $103,188 $0 $0 $0
18 Non-Mon.Accruals $729,745 $106,710 $117,920 $71,385 ($18,173) $99,961 $45,405 $142,049 $62,739 $101,749 $0 $0 $0
19 Total 555 Purchased Power $158,288,828 $14.649,944 $22,918,792 $17,154,312 $15,506,870 $16,498,614 $17,744,546 $19,209,958 $16,654,111 $18,286,103 ($50,422) ($142,000) ($142,000)
555 PURCHASED POWER
555000 $157,652,552 $13,866,745 $21,620,393 $17,220,716 $17,484,550 $17,494,009 $17,252,770 $19,066,877 $16,510,605 $17,135,887 $0 $0 $0
555030 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555200 ($100,880) $0 $0 $0 ($100,880) $0 $0 $0 $0 $0 $0 $0 $0
555312 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555313 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555380 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
555550 $729,745 $106,710 $117,920 $71,385 ($18,173) $99,961 $45,405 $142,049 $62,739 $101,749 $0 $0 $0
555700 $3,141,719 $39,120 $572,008 $585,151 $208,432 $85,450 $1.111.797 $85,200 $28,275 $426,286 $0 $0 $0
20 Solar Select Adjustment ($82,709) ($5,418) ($5,500) ($8,078) ($10,881) ($10,919) ($11,858) ($11,480) ($9,974) ($8,601)Or $0 $0 $0
21 555380 $12,845,233 $1,512,232 $1,370,915 $1,499,825 $1,536,936 $1,516,066 $1,444,087 $1,501,236 $1,064,338 $1,399,598✓ $0 $0 $0
22 Clearwater Adjustment ($12,845,233) ($1,512,232) ($1,370,915) ($1,499,825) ($1,536,936) ($1,516,066) ($1,444,087) ($1,501,236) ($1,064,3" $1,399,598)✓ $0 $0 $0
23 Chelan Adjof LMC vs Contract Price ($3,277,812) $ (3,- $ (87,- $ (53,293) $ ,134,597) $ (681,394) $ (517,921) $ (453,989) $ ((35,709)� ✓
24 Columbia Basin Adj of LMC vs Contract Price ($2,901,916) $ - $ - $ (532,293) $ (1,134,597) $ (681,394) $ (517,923) $ - $ (35,709)
25 Company Absorbed Wind Adjustment ($2,038,376) ($135,963) ($235,489) ($418,244) ($305,473) ($272,299) ($236,388) ($237,714) ($196,806) It
26 Palouse Wind PPA Adjustment ($142,000)✓ ($142,000) ($142,000) ($142,000) R-OS
555710 $979,305 $111,115 $194,678 $88,561 $87,492 $83,461 $99,714 $106,637 $104,459 $103,188 $0 $0 $0
555740 $4,755,200 $671,321 $741,858 $1,138,769 $110,480 $24,793 $378,850 $512,378 $415,579 $669,594 $91,578 $0 $0
$158,288,828 $14,649,944 $22,918,792 $17,154,312 $15,506,870 $16,498,614 $17,744,546 $19,209,958 $16,654,111 $18,286,103 ($50,422) ($142,000) ($142,000)
($682,037)
447 SALES FOR RESALE
27 Short-Term Sales ($106,485,356) ($12,168,965) ($13,083,760) ($14,197,853) ($11,728,570) ($9,705,613) ($11,217,958) ($14,122,714) ($8,895,920) ($11,260,057) ($103,946) $0 $0
28 Nichols Pumping Index Sale ($1,269,953) ($132,824) ($151,283) ($82,969) ($63,712) ($93,333) ($123,074) ($208,636) ($205,428) ($208,694) $0 $0 $0
29 Soverign/Kaiser Load Following $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
30 Pend Oreille DES ($383,464) ($47,098) ($41,677) ($43,507) ($43,870) ($45,562) ($41,049) ($48,770) ($35,815) ($36,116) $0 $0 $0
31 Merchant Ancillary Services ($37,716,376) ($3,467,041) ($4,006,451) ($4,215,854) ($5,077,331) ($4,646,623) ($4,925,362) ($3,557,289) ($3,657,162) ($4,163,263) $0 $0 $0
32 Total 447 Sales for Resale ($145,855,149) ($15,815,928) ($17,283,171) ($18,540,183) ($16,913,483) ($14,491,131) ($16,307,443) ($17,937,409) ($12,794,325) ($15,668,130) ($103,946) $0 $0
447 SALES FOR RESALE
447000 ($70,626,526) ($8,042,952) ($10,073,662) ($8,948,674) ($7,610,973) ($8,776,385) ($11,110,798) ($6,735,870) ($4,509,014) ($4,818,198) $0 $0 $0
33 Deduct Revenue From Solar Select $1,353,842 $64,839 $65,458 $74,296 $106,010 $171,239 $224,635 $256,029 $211,306 $180,030✓ $0 $0 $0
447100 ($7,644,351) ($620,226) $1,031,040 ($2,100,093) ($1,681,328) $1,339,548 $3,629,520 ($4,119,218) ($2,424,294) ($2,699,300) $0 $0 $0
447150 ($20,147,806) ($2,829,559) ($3,357,951) ($1,727,094) ($1,353,212) ($1,884,091) ($2,038,731) ($2,543,716) ($1,921,593) ($2,491,859) $0 $0 $0
447700 ($4,147,268) ($42,410) ($618,313) ($1,075,555) ($458,793) ($56,009) ($1,115,014) ($91,422) ($33,126) ($656,626) $0 $0 $0
447710 ($979,305) ($111,115) ($194,678) ($88,561) ($87,492) ($83,461) ($99,714) ($106,637) ($104,459) ($103,188) $0 $0 $0
447720 ($37,716,376) ($3,467,041) ($4,006,451) ($4,215,854) ($5,077,331) ($4,646,623) ($4,925,362) ($3,557,289) ($3,657,162) ($4,163,263) $0 $0 $0
447740 ($5,947,359) ($767,464) ($128,614) ($458,648) ($750,364) ($555,349) ($871,979) ($1,039,286) ($355,983) ($915,726) ($103,946) $0 $0
($145,855,149) ($15,815,928) ($17,283,171) ($18,540,183) ($16,913,483) ($14,491,131) ($16,307,443) ($17,937,409) ($12,794,325) ($15,668,130) ($103,946) $0 $0
501 FUEL-DOLLARS
34 Kettle Falls Wood-501110 $5,854,173 $933,844 $797,711 $883,284 ($5,108) $0 $678,159 $929,914 $998,929 $637,440 $0 $0 $0
35 Kettle Falls Gas-501120 ($1,821) $287 $1,741 ($962) ($5,401) ($243) $1,539 ($750) $2,678 ($710) $0 $0 $0
36 Colstrip Coal-501140 $23,985,910 $2,521,742 $3,676,147 $2,849,365 $1,696,656 $1,519,144 $1,866,322 $3,612,047 $3,603,486 $2,641,001 $0 $0 $0
37 Colstrip Oil-501160 $173,813 $0 $47,196 $20,870 $11,078 $6,512 $22,187 $65,970 $0 $0 $0 $0 $0
38 Total 501 Fuel Expense $30,012,075 $3,455,873 $4,522,795 $3,752,557 $1,697,225 $1,525,413 $2,568,207 $4,607,181 $4,605,093 $3,277,731 $0 $0 $0
501 FUEL-TONS
39 Kettle Falls 303,306 47,598 41,680 46,433 - - 35,047 47,759 51,900 32,889 - - -
40 Colstrip 656,399 90,120 82,086 78,070 46,696 40,389 51,303 96,920 99,769 71,046 - - -
501 FUEL-COST PER TON
41 Kettle Falls wood $19.62 $19.14 $19.02 $19.35 $19.47 $19.25 $19.38
42 Colstrip coal $27.98 $44.78 $36.50 $36.33 $37.61 $36.38 $37.27 $36.12 $37.17
Page 44
2025 WA ID Actual Deferrals.xlsx ID Monthly 2

Q3 2025 ID PICA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO DEFERRED POWER COST CALCULATION-ACTUAL SYSTEM POWER SUPPLY EXPENSES
Line
No. TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25
547 FUEL
43 NE CT Gas-547213 $4,143 $1,211 $639 ($1,163) ($5,082) ($324) $453 ($907) $1,425 $7,891 $0 $0 $0
44 Boulder Park-547216 $2,263,282 $90,977 $373,870 $266,081 $158,946 $108,083 $249,552 $306,300 $357,945 $351,528 $0 $0 $0
45 Kettle Falls CT-547211 $22,151 $3,074 $3,102 $1,817 $10,082 $454 ($636) $1,272 $753 $2,233 $0 $0 $0
46 Coyote Springs2-547610 $32,166,251 $5,503,409 $4,984,616 $4,197,442 $2,644,029 $1,925,515 $3,360,708 $2,563,637 $3,652,487 $3,334,408 $0 $0 $0
47 Lancaster-547312 $26,224,611 $4,823,423 $4,344,662 $3,664,728 $1,295,217 $689,411 $2,794,405 $2,798,290 $2,993,237 $2,821,238 $0 $0 $0
48 Rathdrum CT-547310 $19,221,500 $3,373,285 $3,237,724 $2,055,231 $1,298,231 $1,262,137 $1,931,468 $2,124,366 $1,926,692 $2,012,366 $0 $0 $0
49 Total 547 Fuel Expense $79,901,938 $13,795,379 $12,944,613 $10,184,136 $5,401,423 $3,985,276 $8,335,950 $7,792,958 $8,932,539 $8,529,664 $0 $0 $0
50 TOTAL NET EXPENSE $122.347.692 $16,085.268 $23,103,029 $12,550,822 $5,692,035 $7,518.172 $12.341,260 $13,672,688 $17.397.418 $14,425,368 ($154,368) ($142,000) ($142,000)
-202501 202502 j 202503 202504 202505 j 202506 202507 202508 j 202509 202510 202511 202512
456 TRANSMISSION REVENUE
51 456100 ED AN ($19,557,191) ($2,462,659) ($2,391,307) ($2,394,241) ($2,129,966) ($2,217,910) ($1,957,539) ($2,114,367) ($1,910,270) ($1,978,932) $0 $0 $0
52 456120 ED AN-BPA Trans. ($693,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) ($77,000) $0 $0 $0
53 456020 ED AN-Sale of excess SPA Trans $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
54 456030 ED AN-Clearwater Trans ($1,353,335) ($154,335) ($154,000) ($154,000) ($148,500) ($148,500) ($148,500) ($148,500) ($148,500) ($148,500) $0 $0 $0
55 456130 ED AN-Ancillary Services Revenue ($979,305) ($111,115) ($194,678) ($88,561) ($87,492) ($83,461) ($99,714) ($106,637) ($104,459) ($103,188) $0 $0 $0
56 456017 ED AN-Low Voltage ($90,567) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) ($10,063) $0 $0 $0
57 456700 ED ID-Low Voltage ($47,097) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) ($5,233) $0 $0 $0
58 456705 ED AN-Low Voltage ($1,334,646) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) ($148,294) $0 $0 $0
59 Total 456 Transmission Revenue ($24,055,141) ($2,968,699) ($2,980,575) ($2,877,392) ($2,606,548) ($2,690,461) ($2,446,343) ($2,610,094) ($2,403,819) ($2,471,210) $0 $0 $0
565 TRANSMISSION EXPENSE
60 565000 ED AN $21,796,301 $2,245,132 $2,246,019 $2,650,847 $2,470,366 $2,393,183 $2,389,631 $2,483,293 $2,492,241 $2,425,589 $0 $0 $0
61 565710 ED AN $53,793 $5,977 $5,977 $5,977 $5,977 $5,977 $5,977 $5,977 $5,977 $5,977 $0 $0 $0
62 Total 565 Transmission Expense $21,850,094 $2,251,109 $2,251,996 $2,656,824 $2,476,343 $2,399,160 $2,395,608 $2,489,270 $2,498,218 $2,431,566 $0 $0 $0
557 Expense
63 557165 ED AN CAISO $170,970 $2,984 $4,818 $26,074 $57,166 $69,241 $4,074 $2,102 $1,853 $2,658 $0 $0 $0
64 557167 ED AN $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
65 557018 ED AN Merchandis $7,429 $4,073 $3,781 ($130) $0 $0 ($295) $0 $0 $0 $0 $0 $0
66 557020 ED AN-Tariff Cost $27,652 $0 $0 $27,652 $0 $0 $0 $0 $0 $0 $0 $0 $0
67 Total 557 ED AN Broker&Related Fees $206,051 $7,057 $8,599 $53,596 $57,166 $69,241 $3,779 $2,102 $1,853 $2,658 $0 $0 $0
537 Expense
68 537000 ED AN-MT Invasive Species $582,498 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722
69 Total 537 ED AN MT Invasive Species $582,498 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $64,722 $0 $0 $0
Other Purchases and Sales
70 Econ Dispatch-557010 $11,521,140 $1,480,819 $2,380,180 $3,023,389 $471,998 $333,049 $385,530 $792,414 $1,425,388 $1,228,373 $0 $0 $0
71 Econ Dispatch-557150 ($2,072,769) ($1,868,318) ($2,621,649) ($651,285) $1,671,560 $1,762,018 $462,563 $169,122 ($587,313) ($409,467) $0 $0 $0
72 Gas Bookouts-557700 $1,624,621 $468,775 $116,900 $309,405 $140,581 $0 $36,270 $485,019 $32,453 $35,218 $0 $0 $0
73 Gas Bookouts-557711 ($1,624,621) ($468,775) ($116,900) ($309,405) ($140,581) $0 ($36,270) ($485,019) ($32,453) ($35,218) $0 $0 $0
74 Intraco Thermal Gas-557730 $6,917,437 $1,155,447 $760,783 $1,030,660 $393,919 $143,763 $206,915 $1,303,214 $1,099,216 $823,520 $0 $0 $0
75 Fuel Dispatch-456010 ($759,611) $224,169 ($56,875) ($357,856) ($469,275) ($99,774) $0 $0 $0 $0 $0 $0 $0
76 Fuel Dispatch-456015 ($13,802,602) ($661,280) ($497,104) ($1,903,363) ($1,941,354) ($1,978,461) ($925,962) ($2,864,806) ($1,260,531) ($1,769,741) $0 $0 $0
77 Other Elm Rev-Extraction Plant Cr-456018 ($412,777) ($42,833) ($50,849) ($44,832) ($55,901) ($40,186) ($44,217) ($48,211) ($49,406) ($36,342) $0 $0 $0
78 Other Elm Rev-Specified Source-456019 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
79 Intraco Thermal Gas-456730 ($2,070,447) ($77,453) ($16,045) ($638,673) ($430,223) ($267,373) ($125,954) ($185,745) ($248,228) ($80,753) $0 $0 $0
80 Fuel Bookouts-456711 $727,843 $61,063 $33,576 $172,721 $89,526 $3,817 $732 $352,768 $4,170 $9,470 $0 $0 $0
81 Fuel Bookouts-456720 ($727,843) ($61,063) ($33,576) ($172,721) ($89,526) ($3,817) ($732) ($352,768) ($4,170) ($9,470) $0 $0 $0
82 Other Purchases and Sales Subtotal ($679,629) $210,551 ($101,559) $458,040 ($359,276) ($146,964) ($41,125) ($834,012) $379.126 ($244,410) $0 $0 $0
83 Misc Revs 456016 ED AN ($103,865) ($900) $0 $44,535 $0 $0 $0 $0 ($147,500) $0 $0 $0 $0
84 REC Revenue Subtotal ($103,865) ($900) $0 $44,535 $0 $0 $0 $0 ($147,500) $0 $0 $0 $0
85 Misc.Power Exp.Actual-557160 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
86 Misc.Power Exp.Subtotal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
87 Wind REC Exp Authorized $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0
88 Wind REC Exp Actual 557395 $803 $52 $71 $50 $61 $94 $108 $135 $116 $116 $0 $0 $0
89 Wind REC Subtotal $803 $52 $71 $50 $61 $94 $108 $135 $116 $116 $0 $0 $0
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2025 WA ID Actual Deferrals.xlsx ID Monthly 3

Q3 2025 ID PCA Quarterly Report
Avista Corp.-Resource Accounting
IDAHO DEFERRED POWER COST CALCULATION-ACTUAL SYSTEM POWER SUPPLY EXPENSES
Line
No. TOTAL Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25
90 456030 ED ID-Clearwater Trans $134,792 $14,308 $15,434 $15,400 $15,400 $14,850 $14,850 $14,850 $14,850 $14,850 $0 $0
91 456380-ED-ID-Clearwater REC Revenue ($827,172) ($84,633) ($107,275) ($89,397) ($88,295) ($99,866) ($96,205) ($96,622) ($100,273) ($64,606) $0 $0
92 Clearwater ($692,380) ($70,325) ($91,841) ($73,997) ($72,895) ($85,016) ($81,355) ($81,772) ($85,423) ($49,756) $0 $0 $0
93 Net Resource Optimintlon ($782,691) $209,703 ($101,488) $502,625 ($359,215) ($146,870) ($41,017) ($833,877) $231,742 ($244,294) $0 $0 $0
94 EIM Incremental O&M Costs(Idaho share) $251,244 $32,205 $26,428 $25,328 $32,087 $29,628 $39,629 $34,606 $45,542 R $14,209)
95 Adjusted Actual Net Expense $119,707,367 $15,611,040 $22,280,870 $12,902,528 $5,283,695 $7,158,576 $12,276,283 $12,737,645 $17,750,253 $14,144,845 ($154,368) ($142,000) ($142,000)
QA 12,788.10 -
0.90 = If
©14,209.00 T+
Page 46
2025 WA ID Actual De(errals.xlsx ID Monthly 4

Q3 2025 ID PCA Quarterly Report
Avista Corp.-Resource Accounting
Idaho Electric Jurisdiction
Power Costs Adjustment (PCA) - Load Change Adjustment - 2025
Retail Revenue Credit excluding
Clearwater-MWh Jan-25 Feb-25 Mar-25 Apr-25 May-25 Jun-25 Jul-25 Aug-25 Sep-25 Oct-25 Nov-25 Dec-25 YTD
Total Billed Sales 312,860 309,308 274,035 255,324 221,646 237,222 257,843 268,504 263,718✓ 225,023 2,400,460
Deduct Prior Month Unbilled (137,264) (145,445) (132,541) (124,764) (106,829) (119,536) (127,614) (150,599) (149,750)✓ (125,641) (1,194,342)
Add Current Month Unbilled 145,445 132,541 124,764 106,829 119,536 127,614 150,599 149,750 125,641✓ 125,641 1,182,719
Total Retail Sales 321,041 296,404 266,258 237,389 234,353 245,300 280,828 267,655 239,609 225,023 2,388,837
Test Year Consumption 304,450 275,917 276,088 250,222 227,023 225,845 256,211 254,893 215,718✓ 232,623✓ 269,741 ✓ 307,917✓ 2,286,367
Difference from Test Year 16,591 20,487 (9,830) (12,833) 7,330 19,455 24,617 12,762 23,891 ✓ (7,600) 102,470
Load Change Adjustment Rate- $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $24.50 $23.67✓ $23.67✓ $23.67✓ $23.67 ✓
$1M W h
Total Load Change Adjustment-$ $406,480 $501,932 ($240,835) ($314,409) $179,585 $476,648 $603,117 $312,669 R-031$565,500✓ ($179,892) $2,490,687
Page 47
Page 4 of 4

Q3 2025 ID PCA Quarterly Report
Electric Revenue Report by Revenue Class Data Source:Financial Reporting
Data Updated Daily
Accounting Period:202509✓ State Code:ID✓
Rate Schedule Desc Meter Qty Usage Qty Revenue Amt YTD Meter Qty YTD Usage I YTD Revenue Amt
0001-RESIDENTIAL 0 0 (263,615) 0 0 (2,511,679)
0011-GENERAL SERVICE 0 0 (201,841) 0 0 (1,694,879)
0012-RESID&FARM-GEN SERV 0 0 (6,767) 0 0 (71,516)
0021-LARGE GENERAL SERV 0 0 (17,073) 0 0 (185,416)
0022-RESID&FRM-LGE GEN SE 0 0 (1,564) 0 0 (13,654)
0025-EXTRA LGE GEN SERV 0 0 (73,671) 0 0 (651,557)
0031-PUMPING SERVICE 0 0 (20,543) 0 0 (127,668)
0032-PUMPING SVC RES&FRM 0 0 (1,702) 0 0 (12,005)
0042-CO OWND ST LTS SO VA 0 0 (1,053) 0 0 (9,479)
0044-CST OWND ST LT SO VA 0 0 (49) 0 0 (458)
0045-CUST OWND ST LT ENGY 0 0 (56) 0 0 (508)
0046-CUST OWND ST LT S V 0 0 (185) 0 0 (1,697)
0047-AREA LIGHT-COM&INDUS 0 0 (19) 0 0 (331)
0048-AREA LGHT-FARM&RESID 0 0 (144) 0 0 _ (1,359)
0049-AREA LGHT-HI PRIES SO 0 0 (413) 0 0 (3,702)
025 EXTRA LARGE GEN SERVICE/POTLATCH 0 0 (59,843) 0 0 (617,843)
10023-DCFC-ID 0 0 (46) 0 0 (302)
Overall-Summary 0 01 (648,585)1 0 904,052)1
Page 1 of 3 Run Date: Oct 6,2025
IFor Internal Use Only
0.995661✓Settlement Revenue Conversion Factor Changes w/Base GRC
R-021 (645,771)✓
CF update: GRC effective 9.1.25 - 8.31.27 ✓
H:\Power Deferrals\Power Deferral Journals\2_ID PCA\2025 ID PCA\Cognos Reports\202509 Revenue_RateSch_CM_YTD for ID PCA.xlsx lOP�2025$8:59 AM

Q3 2025 ID PCA Quarterly Report
Revenue By Revenue Class Data Source: Financial Reporting
Electric Data Updated Daily
State Code:ID
Accounting Period Service I Revenue Class Revenue Class Desc Meter Qty Usage Qty Revenue Amt I YTD Average Meters YTD Usage YTD Revenue Amt
202509 ED 01 01 RESIDENTIAL 129,395 110,981,327 13,283,446 128,894 1,058,949,408 121,932,768
21 21 FIRM COMMERCIAL 19,375 96,812,475 9,160,616 19,280 802,610,869 73,148,819
31 31 FIRM-INDUSTRIAL 314 84,267,925 4,472,525 316 882,844,549 44,946,346
39 39 FIRM-PUMPING-IRRIGATION ONLY 42 351,409 37,388 39 3000901 310,357
51 51 LIGHTING-PUBLIC STREET AND HIWAY 203 597,439 268,306 203� 5:115:465 2,359,824
80 80 INTERDEPARTMENT REVENUE 53 133,881 12,948 53 1,884,286 173,827
83 83 MISC-SERVICE REVENUE SNP 0 0 9,516 0 0 84,088
85 85 MISC-RENT FROM ELECTRIC PROPERTY 0 0 9,548 0 0 85,928
OD OD Other Electric Direct 0 0 1,100 0 0 9,500
RP RP Rent Permits 0 0 1,000 0 0 2,735
ED-Summary 149,382 293,144,456 27,256,393 148,786 2,754,405,478 243,054,193
202509-Summary 149,382 293,144,456 27,256,393 148,786 2,754,405,478 243,054,193
Overall-Summary 149,382 293,144,456 v 27,256,393 148,786 2,754,405,478 243,054,193
Page 2 of 4 Run Date: Oct 6,2025
Total Billed Sales-input tab,deferral calc workbook
IFor Internal Use Only
Pa
H:\Power Deferrals\Power Deferral 3ournals\2_ID PCA\2025 ID PCA\Cognos Reports\202509 Revenue By Revenue ffassQ D.xlsx

Q3 2025 ID PCA Quarterly Report
Current Month Journal Entry
Jurisdiction: ID,/
Revenue Class Revenue Class Desc Town Code Revenue Class Rate Schedule Gross Unbilled kWh Total Unbilled+Basic Charge
3800 01 001 34,698,454 $4,340,731
01 01 RESIDENTIAL 3800 01 011 0
3800 01 012 890,754 $130,476
3800 01 022 205,912 $18,191
3800 01 032 120,333 $18,592
3800 21 011 25,615,7591 $2,363,062
21 21 FIRM COMMERCIAL 3800 21 021 1,581,112 $119,064
3800 21 025 5,740,027 $362,799
0
3800 21 031 2,203,065 $251,797
31 FIRM-INDUSTRIAL 3800 31 011 911,012 $79,914
3800 31 021 666,200 $49,856
31 FIRM-INDUSTRIAL 3800 31 025 23,536,728 $1,513,207
3800 31 031 488,795 $55,923
31 31 FIRM INDUSTRIAL 3800 31 025P 28,982,710 $1,589,181
3800 31 025PG 38,695,000 $1,399,598
0 i
21 -Summary
i
31 -Summary
:i
ID-Summary 164,335,860
Unbilled-input tab, deferral calc workbook
G:\CLOSE\202509\Revenue\REVUNBL\REVUNBLD - E\SOX Electric Unbilled.xlsx 10/6/20Aag9.96 AM

Q3 2025 ID PCA Quarterly Report
Avista Corporation Journal Entry Printed 10/03/2025 at 9:35 AM
Journal: 240-EIM DEFERRAL Effective Date: 202509v
Team: Energy Delivery Accounting Last Saved by: Brysen Hoff Last Update: 10/03/2025 9:34 AM
Type: C Submitted by: Brysen Hoff Approval Requested: 10/03/2025 9:34 AM
Category: DJ Approved by:
Currency: USD
Seq. Co. FERC Ser. Jur. S.I. Debit Credit Comment
10 001 431230-INTEREST ON REG DEFERRALS-ST ED WA DL 1,629.75 0.00 Provisional EIM WA-202509 Interest
20 001 229030-ACCUM PROV RATE REFUND-EIM ED WA DL 17,171.73 0.00 Provisional EIM WA-202509 Deferral
CAP
30 001 184057-CLEARING ACCT-ENERGY DLTVERY ZZ ZZ DL 0.00 18,801.48 Provisional EIM WA-202509 Deferral
ACCT
Totals: 18,801.48 18,801.48
Seq. Project Task Exp. Org Quantity Co. FERC Ser. Jur.
10 03805834-EIM Deferral-ID 407434-EIM Deferred O&M 885 D57- 12,788.10,e001 182386-REGULATORY ASSET ID ED ID
Miscellaneous Misc PCA DEFERRAL 2
Comment:EIM PCA Deferral ID-202509
20 02807414-EIM Interest Deferral-WA 407439-Amort EIM Deffrral 885 D57- (18,801.48) 001 184057-CLEARING ACCT-ENERGY ZZ ZZ
Miscellaneous Misc DLTVERY ACCT
Comment:Provisional EIM WA-202509 Amortization
Total: (6,013.38) 1�
Explanation: IFIY 10/03/2025
Pr ared b ryse
off Date
To record EIM Deferred costs in accordance with IPUC Order No.34606- 10/03/2025
Post costs of which 90%are to be deferred through the PCA.
Reviewed by 61 Date
Approved for Entry Date
Corporate Accounting use Only
Page 1 of 1
Page 51

Q3 2025 ID PCA Quarterly Report
From: Garbarino,Marcus
To: Parsons,Amy; Hossack,Jennifer
Cc: Andrews,Liz; Miller,Joe
Subject: ID PCA Base
Date: Tuesday,October 7,2025 1:02:34 PM
Attachments: Appendix A-PCA Base Updated LCAR Load 10-7-2025.pdf
Appendix A-PCA Base Undated LCAR Load 10-7-2025.xlsx
imaae001.Dna
imaoe002.pno
imaae003.Dna
imaoe004.pno
Hi Amy,
v'
Attached is the corrected Authorized PCA base workpaper for the 2025 ID GRC using the loads
included in the case and approved by the Commission. In the version of this workpaper
included with our compliance filing, authorized Idaho retail sales volumes had not been
updated from the last general rate case to reflect the volumes included in the current general
rate case filing.This line does not impact authorized power supply expenses or the LCAR
calculation, as both used the correct retail sales volumes.
We will be reaching out to Commission Staff to see how to proceed.We believe that Staff will
either have us just use the correct loads (included in the attached version)for purposes of
calculating the LCAR deferral or have us file a request to revise/amend the PCA Base
workpaper to reflect the loads used and approved in the case.
Either way,we believe the loads in the attached version should be used to calculate the
deferral effective 9/1/25 given those are the correct loads from the case and if we end up
needing to revise/amend that workpaper,we believe the Commission will likely approve it.
Thank you noticing the approved volumes looked off and bringing it to our attention!
Let us know if you have any questions.
Thank you,
Marcus Garbarino, CPA
Manager of Regulatory Affairs
1411 E Mission Ave MSC-23, Spokane, WA, 99202
P 509.495.2567
www.myavista.com Ei d
Page 52

Q3 2025 ID PCA Quarterly Report
Avista Corp
PCA Authorized Expense and Retail Sales(Annual)- Rate Year 1 (effective September 1,2025)
Based on Pro forma 9/1/2025-8/31/2026
7/1/2023-6/30/2024 Historic Normalized Loads
PCA Authorized Power Supply Expense-System Numbers(1)
Total r�-S�e Oct Nov Dec Jan Feb Mar Air Mav Jun Jul A�cu
1 1
Account 555-Purchased Power $190,259,0680, $12,753,120 $13,316,871 $11,607,682 $12,096,10610 $22,800,890 $14,553,299 $14,292,153 $16,075,993 $16,801,795 $16,631,043 $17,031,155 $22,298,963
Account 501-Thermal Fuel $19,215,574, $3,968,536 $3,155,810 $3,272,978 $3,539,2251 $679,663 $922,483 $869,703 $433,873 $101,373 $330,873 $926,933 $1,014,123
Account 537-MT Invasive Species $780,0001 $65,000 $65,000 $65,000 $65,0001 $65,000 $65,000 $65,000 $65,000 $65,000 $65,000 $65,000 $65,000
Account 547-Natural Gas Fuel $104,787,5161 $8,781,685 $7,732,236 $10,506,214 $13,732,592, $8,712,646 $11,748,648 $9,927,317 $5,970,843 $4,074,001 $4,753,424 $8,735,538 $10,112,369
Account 557-Other Expenses $958,465j $79,872 $79,872 $79,872 $79,872j $79,872 $79,872 $79,872 $79,872 $79,872 $79,872 $79,872 $79,872
Account 565-Transmission Expense $32,922,3341 $2,743,528 $2,743,528 $2,743,528 $2,743,5281 $2,743,528 $2,743,528 $2,743,528 $2,743,528 $2,743,528 $2,743,528 $2,743,528 $2,743,528
Account 456-Other Revenue $17,468,723! $1,337,159 $1,088,750 $1,265,257 $2,162,51101 $3,582,523 $1,723,440 $1,121,053 $589,881 $1,040,209 $994,579 $1,252,789 $1,310,571
I I
Account 447-Sale for Resale -$172,461,699j -$19,953,584 -$15,137,594 -$18,382,654 -$26,178,834j -$1,416,534 -$13,038,624 -$9,709,334 -$11,804,984 -$14,837,724 -$17,413,234 -$15,799,934 -$8,788,664
Power Supply Expense $193,929,9811 $9,775,317 $13,044,474 $11,157,877 $8,240,0011 $37,247,588 $18,797,646 $19,389,292 $14,154,006 $10,068,054 $8,185,084 $15,034,881 $28,835,762
I I
Account 456-Transmission Revenue(2) -$37,482,16010 -$3,099,146 -$3,125,305 -$2,986,534 -$3,189,45810 -$3,183,581 -$3,191,635 -$3,172,317 -$3,771,567 -$2,633,999 -$2,846,226 -$3,400,571 -$2,881,821
i i
Total Authorized Expense $156,447,821, $6,676,171 $9,919,169 $8,171,343 $5,050,5431 $34,064,008 $15,606,011 $16,216,975 $10,382,439 $7,434,055 $5,338,858 $11,634,310 $25,953,940
Shaping Adjustment $OI$ 3,839,288 $ 4,121,443 $ 5,998,200 $ 9,178,058I$ 4,507,858 $ 60,685 $ 3,879,221 $ 10,013 $ 1,645,892 $ 290,881 $ 5,544,900 $ 7,920,697
Adjusted Authorized $156,447,821,0 $10,515,459✓$14,040,612✓ $14,169,543✓$14,228,601N$29,556,150 $15,666,695 $12,337,755 $10,392,452 $5,788,163 $5,629,739 $6,089,410 $18,033,244
Idaho Only(no adjustment for Directly assigne( $55,570,2661 $3,735,091 $4,987,225 $5,033,022 $5,053,9991 $10,498,344 $5,564,810 $4,382,370 $3,691,399 $2,055,955 $1,999,683 $2,162,958 $6,405,408
Shaping Adjustment I I
PCA Authorized Idaho Retail Sales(3) 1 1
Total Idaho Retail Sales,MWh 3,136,9251__215,718✓ 232,623✓_._ 269,741✓,_307,91 l✓ 326,882 281,061 274,963 240,388 233,037 224,084 273,011 257,501
RY1 Load Change Adjustment Rate(4', $23.67/MWh✓ $52,954,214 rounding difference with deferral calc workbool,
RY2 Load Change Adjustment Rate(4', $26.09/MWh
(1)Multiply number by ROO current production/transmission allocation ratio of 35.52%
(2)Transmission Revenue as discussed by Company witness Mr.Dillon.
(3)Note totals may vary slightly from adjustment due to rounding.
(4)Twelve months ended June 30,2024 normalized monthly retail sales.
AVU-E-25-01 SETTLEMENT STIPULATION APPENDIX A- REVISED ✓ Page 1 of 1
Page 53

Q3 2025 ID PCA Quarterly Report
AVISTA UTILITIES
Revenue Conversion Factor
Idaho-Electric System
TWELVE MONTHS ENDED JUNE 30,2024
Line
No. Description Factor
1 Revenues 1.000000 1.000000
Expenses:
2 Uncollectibles 0.002212 0.002212
3 Commission Fees 0.002127 0.002127
4 Idaho Income Tax 0.000000
5 Total Expenses 0.004339 0.004339
6 Net Operating Income Before FIT 0.995661 0 0.995661
7 Federal Income Tax @ 21% 0.209089
8 REVENUE CONVERSION FACTOR 0.786572
9 Gross Up Factor for Revenue Related Expenses 1.0044
AVU-E-25-01 SETTLEMENT STIPULATION APPENDIX B Page 5 - Rev Conversion Factor
Page 54

Q3 2025 ID PCA Quarterly Report
Revise Net Power Supply Expense. This adjustment revises Idaho net power supply expenses as
discussed below, decreasing the Idaho electric overall revenue requirement by $4,611,000. See
Power Cost Adjustment(PCA) discussion at¶11 below.'
i. Net Power Supply Correction. The Settling Parties agree to reflect corrections to net
power supply expense, from that filed by the Company, reducing system net power
supply expense by $11.2 million, and Idaho allocated net power supply expense by $4.0
million.
R-0
ii. Palouse Wind. The Settling Parties agree to remove the cost of the Palouse Windt Power
Purchase Agreement("PPA") and replace it with the optimized cost of the Company's
other resources to determine the Company's Net Power Supply Expense both in base
rates and in the Power Cost Adjustment(PCA) mechanism. This adjustment decreases
system net power supply expense by $1.7 million and Idaho's share by $605,000 in base
rates and in actual cost in the PCA.**
iii. Shaping Adjustment. The Parties agree to include a monthly"shaping" adjustment of net
power supply expenses for the period September 1, 2025 through August 31, 2026, to
better reflect and match recovery of costs,using the monthly percentage of net power
supply expense reflected in Rate Year 2 (September 1, 2026 through August 31, 2027).
This "shaping" adjustment, reflected in Appendix A, has no impact on annual system or
Idaho share of net expenses.
**Andrews Supporting Settlement Testimony: This will reflect removing the contract cost and
generation of the Palouse Wind PPA and replace it with the energy dispatched from other
Company resources. In RY1, September 1, 2025 through August 31, 2026, when calculating and
recording the monthly PCA impact,Avista will reduce system net actual versus authorized power
supply expense by $1.7 million (approximately $142,000 monthly)prior to applying the
90%/l0% sharing allocation, to reflect this change within the PCA. This adjustment does not
impact Rate Year 2.
' Idaho's share of net power supply costs reflects a production and transmission(P/T)ratio of 35.52%.
2 The Palouse Wind PPA is a 30-year contract that was executed in 2011 by the Company who purchases all of its
output (105 MW nameplate capacity) and environmental attributes. The project began commercial operation in
December 2012.
Page 55