20260731Brandon Exhibit AMB-1.pdf

ANNI GLOGOVAC
COUNSEL FOR REGULATORY AFFAIRS RECEIVED
AVISTA CORPORATION JULY 31, 2026
1411 E. MISSION AVENUE IDAHO PUBLIC
UTILITIES COMMISSION
P.O. BOX 3727
SPOKANE, WASHINGTON 99220
PHONE: [phone]
[e-mail]
BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION
IN THE MATTER OF THE POWER COST ) CASE NO. AVU-E-26-05
ADJUSTMENT (PCA) ANNUAL RATE )
ADJUSTMENT FILING OF AVISTA ) EXHIBIT NO. AMB-1
CORPORATION ) ANNETTE M. BRANDON
FOR AVISTA CORPORATION

Exhibit AMB-1
AVISTA UTILITIES
IDAHO ELECTRIC
IMPACT OF PROPOSED SCHEDULE 66 PCA CHANGE
PROPOSED RATE TO BE EFFECTIVE OCTOBER 1,2026
(000s of Dollars)
(000s of kWh) Total Billed Percent
Revenue Proposed change
Line Type of Schedule Forecasted at Present Sch.66 on Billed
No. Service Number Kilowatt-hours Rates Change Revenue
(a) (b) (c)(1) (d) (e) (f)
1 Residential 1 1,357,313 $ 174,917 $ 2,137,551 1222.0%
2 General Service 11,12 962,222 $ 103,092 $ 1,515,346 1469.9%
3 Large General Service 21,22 95,546 $ 11,156 $ 150,470 1348.8%
4 Extra Large General Service 25 348,913 $ 24,076 $ 549,481 2282.3%
5 Clearwater 25P 342,572 $ 19,825 $ 539,496 2721.3%
6 Pumping Service 31,32 65,718 $ 8,697 $ 103,495 1190.0%
7 Street&Area Lights 42-49 9,377 $ 4,271 $ 14,767 345.8%
8 Total 3,181,661 $ 346,034 $ 5,010,607 1448.0%
check 1448.0%
9 Proposed rate $ 1.57183 $ 5,001,017
10 Present rate(AVU-E-24-07,Order No.36339) $ (0.00301) $ (9,576)
11 Rate Change $ 1.57484 $ 5,010,593
Proposed rate
12 Total Amortization and Deferral Balance including interest thru 9/30/26 $ 4,979,318
13 Conversion factor(Case No.AVU-E-25-01: Per Final Stipulation&Settlement) 0.995661
14 Revenue Requirement 5,001,017
15 kWh's from above 3,181,661
16 Proposed rate: $ 1.57183
(1) Source: Calendar Load forecast for the twelve month period October 1,2025-September 30,2026
Exhibit AMB-1 Page 1 of 1

Twenty-Eighth Revision Sheet 66
Canceling
I.P.U.C. No.28 Twenty-Seventh Revision Sheet 66
AVISTA CORPORATION
d/b/a Avista Utilities
SCHEDULE 66
TEMPORARY POWER COST ADJUSTMENT - IDAHO
APPLICABLE:
To Customers in the State of Idaho where the Company has electric service
available. This Power Cost Adjustment shall be applicable to all retail customers for
charges for electric energy sold. This Rate Adjustment is designed to recover or
rebate a portion of the difference between actual and allowed net power supply costs.
MONTHLY RATE:
The energy charges of electric Schedules 1, 11, 12, 21, 22, 25, 25P, 31, 32, and
42-49 are to be increased by 0.1570 per kilowatt-hour in all blocks of these rate
schedules.
SPECIAL TERMS AND CONDITIONS:
The rates set forth under this Schedule are subject to periodic review and
adjustment by the IPUC based on the actual balance of deferred power costs.
Service under this schedule is subject to the Rules and Regulations contained
in this tariff.
The above Rate is subject to increases as set forth in Tax Adjustment
Schedule 58.
Issued July 31, 2026 Effective October 1, 2026
Issued by Avista Utilities
B(y� Patrick Ehrbar— Director of Regulatory Affairs