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BENEFIT PLANS: | 12 Months Ended
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Dec. 31, 2025
Retirement Benefits, Description [Abstract] |
Benefit Plans | BENEFIT PLANS Idaho Power sponsors defined benefit and other postretirement benefit plans that cover the majority of its employees. Idaho Power also sponsors a defined contribution 401(k) employee savings plan and provides certain post-employment benefits. Pension Plans Idaho Power has a noncontributory defined benefit pension plan (pension plan) and two nonqualified defined benefit plans for certain senior management employees, the SMSP. Idaho Power also has a nonqualified defined benefit pension plan for directors that was frozen in 2002. Remaining vested benefits from that plan are included with the SMSP in the disclosures below. The benefits under these plans are based on years of service and the employee's final average earnings. The following table summarizes the changes in benefit obligations and plan assets of these plans (in thousands of dollars):
|  | Pension Plan |  | SMSP
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Change in projected benefit obligation: |  |  |  |  |  |  |  |
Benefit obligation at January 1 |  | $ | 998,166 |  |  | $ | 1,028,016 |  |  | $ | 102,318 |  |  | $ | 105,809 |
Service cost |  | 31,774 |  |  | 33,992 |  |  | 1,172 |  |  | 1,051 |
Interest cost |  | 56,151 |  |  | 52,181 |  |  | 5,640 |  |  | 5,332 |
Actuarial loss (gain) |  | 5,237 |  |  | (65,972) |  |  | 2,401 |  |  | (3,321) |
Plan amendment |  | — |  |  | — |  |  | 7 |  |  | 15 |
Benefits paid |  | (52,309) |  |  | (50,051) |  |  | (6,900) |  |  | (6,568) |
Projected benefit obligation at December 31 |  | 1,039,019 |  |  | 998,166 |  |  | 104,638 |  |  | 102,318 |
Change in plan assets: |  |  |  |  |  |  |  |
Fair value at January 1 |  | 951,142 |  |  | 917,513 |  |  | — |  |  | — |
Actual return on plan assets |  | 104,542 |  |  | 63,680 |  |  | — |  |  | — |
Employer contributions |  | 20,000 |  |  | 20,000 |  |  | — |  |  | — |
Benefits paid |  | (52,309) |  |  | (50,051) |  |  | — |  |  | — |
Fair value at December 31 |  | 1,023,375 |  |  | 951,142 |  |  | — |  |  | — |
Funded status at end of year |  | $ | (15,644) |  |  | $ | (47,024) |  |  | $ | (104,638) |  |  | $ | (102,318) |
Amounts recognized in the balance sheet consist of: |  |  |  |  |  |  |  |
Other current liabilities |  | $ | — |  |  | $ | — |  |  | $ | (6,855) |  |  | $ | (6,827) |
Noncurrent liabilities |  | (15,644) |  |  | (47,024) |  |  | (97,783) |  |  | (95,491) |
Net amount recognized |  | $ | (15,644) |  |  | $ | (47,024) |  |  | $ | (104,638) |  |  | $ | (102,318) |
Amounts recognized in AOCI consist of: |  |  |  |  |  |  |  |
Net loss |  | $ | 13,142 |  |  | $ | 43,516 |  |  | $ | 18,154 |  |  | $ | 16,442 |
Prior service cost |  | 18 |  |  | 24 |  |  | 1,780 |  |  | 1,995 |
Subtotal |  | 13,160 |  |  | 43,540 |  |  | 19,934 |  |  | 18,437 |
Less amount recorded as regulatory asset(1) |  | (13,160) |  |  | (43,540) |  |  | — |  |  | — |
Net amount recognized in AOCI |  | $ | — |  |  | $ | — |  |  | $ | 19,934 |  |  | $ | 18,437 |
Accumulated benefit obligation |  | $ | 895,190 |  |  | $ | 863,705 |  |  | $ | 99,105 |  |  | $ | 96,487 |
(1) Changes in the funded status of the pension plan that would be recorded in AOCI for an unregulated entity are recorded as a regulatory asset for Idaho Power as Idaho Power believes it is probable that an amount equal to the regulatory asset will be collected through the setting of future rates. The actuarial losses reflected in the benefit obligations for the pension and SMSP plans in 2025 are due primarily to actual demographic experience varying from assumed for both plans, and a decrease in the assumed discount rate of the SMSP plan and partially offset by an increase in the assumed discount rates of the pension plan from December 31, 2024 to December 31, 2025. The actuarial gains reflected in the benefit obligations for the pension and SMSP plans in 2024 are due primarily to increases in the assumed discount rates of both plans from December 31, 2023 to December 31, 2024. For more information on discount rates, see “Plan Assumptions” below in this Note 12. As a non-qualified plan, the SMSP has no plan assets. However, Idaho Power has a rabbi trust designated to provide funding for SMSP obligations. The rabbi trust holds investments in marketable securities and corporate-owned life insurance. The recorded value of these investments was approximately $172.1 million and $159.1 million at December 31, 2025 and 2024, respectively, and is reflected in Investments and in Company-owned life insurance on the consolidated balance sheets. The following table shows the components of net periodic pension cost for these plans (in thousands of dollars). For purposes of calculating the expected return on plan assets, the market-related value of assets is equal to the fair value of the assets.
|  | Pension Plan |  | SMSP
|  | 2025 |  | 2024 |  | 2023 |  | 2025 |  | 2024 |  | 2023
Service cost |  | $ | 31,774 |  |  | $ | 33,992 |  |  | $ | 29,843 |  |  | $ | 1,172 |  |  | $ | 1,051 |  |  | $ | 612 |
Interest cost |  | 56,151 |  |  | 52,181 |  |  | 51,277 |  |  | 5,640 |  |  | 5,332 |  |  | 5,322 |
Expected return on assets |  | (68,931) |  |  | (66,533) |  |  | (61,728) |  |  | — |  |  | — |  |  | — |
Amortization of net loss |  | — |  |  | 1,700 |  |  | — |  |  | 690 |  |  | 1,312 |  |  | 570 |
Amortization of prior service cost |  | 6 |  |  | 6 |  |  | 6 |  |  | 221 |  |  | 220 |  |  | 219 |
Net periodic pension cost |  | 19,000 |  |  | 21,346 |  |  | 19,398 |  |  | 7,723 |  |  | 7,915 |  |  | 6,723 |
Regulatory deferral of net periodic pension cost(1) |  | (18,159) |  |  | (20,425) |  |  | (18,553) |  |  | — |  |  | — |  |  | — |
Previously deferred pension cost recognized(1) |  | 35,182 |  |  | 35,182 |  |  | 17,154 |  |  | — |  |  | — |  |  | — |
Net periodic pension cost recognized for financial reporting(1)(2) |  | $ | 36,023 |  |  | $ | 36,103 |  |  | $ | 17,999 |  |  | $ | 7,723 |  |  | $ | 7,915 |  |  | $ | 6,723 |
(1) Net periodic pension costs for the pension plan are recognized for financial reporting based upon the authorization of each regulatory jurisdiction in which Idaho Power operates. Under an IPUC order, the Idaho portion of net periodic pension cost is recorded as a regulatory asset and is recognized in the income statement as those costs are recovered through rates. (2) Of total net periodic pension cost recognized for financial reporting $37.8 million, $35.9 million, and $18.2 million respectively, was recognized in "Other operations and maintenance" and $6.0 million, $8.1 million, and $6.5 million respectively, was recognized in "Other income, net" on the consolidated statements of income of the companies for the twelve months ended December 31, 2025, 2024, and 2023. The following table shows the components of other comprehensive income (loss) for the plans (in thousands of dollars):
|  | Pension Plan |  | SMSP
|  | 2025 |  | 2024 |  | 2023 |  | 2025 |  | 2024 |  | 2023
Actuarial gain (loss) during the year |  | $ | 30,374 |  |  | $ | 63,119 |  |  | $ | (25,071) |  |  | $ | (2,401) |  |  | $ | 3,320 |  |  | $ | (6,517) |
Plan amendment service cost |  | — |  |  | — |  |  | — |  |  | (7) |  |  | (15) |  |  | (11) |
Reclassification adjustments for: |  |  |  |  |  |  |  |  |  |  |  |
Amortization of net loss |  | — |  |  | 1,700 |  |  | — |  |  | 690 |  |  | 1,312 |  |  | 570 |
Amortization of prior service cost |  | 6 |  |  | 6 |  |  | 6 |  |  | 221 |  |  | 220 |  |  | 219 |
Adjustment for deferred tax effects |  | (7,604) |  |  | (16,686) |  |  | 6,452 |  |  | 145 |  |  | (1,245) |  |  | 1,477 |
Adjustment due to the effects of regulation |  | (22,776) |  |  | (48,139) |  |  | 18,613 |  |  | — |  |  | — |  |  | — |
Other comprehensive income (loss) recognized related to pension benefit plans |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | (1,352) |  |  | $ | 3,592 |  |  | $ | (4,262) |
The following table summarizes the expected future benefit payments of these plans (in thousands of dollars):
|  | 2026 |  | 2027 |  | 2028 |  | 2029 |  | 2030 |  | 2031-2035
Pension Plan |  | $ | 53,000 |  |  | $ | 54,713 |  |  | $ | 56,371 |  |  | $ | 58,110 |  |  | $ | 59,898 |  |  | $ | 331,936 |
SMSP |  | 6,855 |  |  | 6,883 |  |  | 7,079 |  |  | 7,360 |  |  | 7,438 |  |  | 37,939 |
Idaho Power’s funding policy for the pension plan is to contribute at least the minimum required under the Employee Retirement Income Security Act of 1974 (ERISA) but not more than the maximum amount deductible for income tax purposes. In 2025, 2024, and 2023, Idaho Power elected to contribute more than the minimum required amounts in order to bring the pension plan to a more funded position, to reduce future required contributions, and to reduce Pension Benefit Guaranty Corporation premiums. As of the date of this report, IDACORP and Idaho Power have no estimated minimum required contributions to the pension plan for 2026. Depending on market conditions and cash flow considerations in 2025, Idaho Power expects that it may contribute up to $30 million to the pension plan during 2026 in order to help balance the regulatory collection of these expenditures with the amount and timing of contributions and to mitigate the cost of being in an underfunded position. Postretirement Benefits Idaho Power maintains a defined benefit postretirement benefit plan (consisting of health care and death benefits) that covers all employees who were enrolled in the active-employee group plan at the time of retirement as well as their spouses and qualifying dependents. Retirees hired on or after January 1, 1999, have access to the standard medical option at full cost, with no contribution by Idaho Power. Benefits for employees who retire after December 31, 2002, are limited to a fixed amount, which has limited the growth of Idaho Power’s future obligations under this plan. The following table summarizes the changes in benefit obligation and plan assets (in thousands of dollars):
|  | 2025 |  | 2024
Change in accumulated benefit obligation: |  |  |  |
Benefit obligation at January 1 |  | $ | 54,604 |  |  | $ | 56,064 |
Service cost |  | 672 |  |  | 698 |
Interest cost |  | 2,973 |  |  | 2,824 |
Actuarial loss (gain) |  | 1,976 |  |  | (778) |
Benefits paid(1) |  | (4,714) |  |  | (4,204) |
Benefit obligation at December 31 |  | 55,511 |  |  | 54,604 |
Change in plan assets: |  |  |  |
Fair value of plan assets at January 1 |  | 31,128 |  |  | 31,804 |
Actual return on plan assets |  | 4,381 |  |  | 4,669 |
Employer contributions(1) |  | 736 |  |  | (1,141) |
Benefits paid(1) |  | (4,714) |  |  | (4,204) |
Fair value of plan assets at December 31 |  | 31,531 |  |  | 31,128 |
Funded status at end of year (included in noncurrent liabilities) |  | $ | (23,980) |  |  | $ | (23,476) |
(1) Contributions and benefits paid are each net of $2.3 million and $2.3 million of plan participant contributions for 2025 and 2024, respectively. Amounts recognized in AOCI consist of the following (in thousands of dollars):
|  | 2025 |  | 2024
Net gain |  | $ | (28,207) |  |  | $ | (29,353) |
Prior service cost |  | 3,262 |  |  | 4,636 |
Subtotal |  | (24,945) |  |  | (24,717) |
Less amount recognized in regulatory assets |  | 24,945 |  |  | 24,717 |
Net amount recognized in AOCI |  | $ | — |  |  | $ | — |
The net periodic postretirement benefit cost was as follows (in thousands of dollars):
|  | 2025 |  | 2024 |  | 2023
Service cost |  | $ | 672 |  |  | $ | 698 |  |  | $ | 658 |
Interest cost |  | 2,973 |  |  | 2,824 |  |  | 2,980 |
Expected return on plan assets |  | (1,786) |  |  | (1,831) |  |  | (1,650) |
Amortization of net loss |  | (1,765) |  |  | (1,494) |  |  | (1,237) |
Amortization of prior service cost |  | 1,374 |  |  | 1,548 |  |  | 1,665 |
Net periodic postretirement benefit cost |  | $ | 1,468 |  |  | $ | 1,745 |  |  | $ | 2,416 |
The following table shows the components of other comprehensive income for the plan (in thousands of dollars):
|  | 2025 |  | 2024 |  | 2023
Actuarial gain during the year |  | $ | 619 |  |  | $ | 3,616 |  |  | $ | 7,572 |
Reclassification adjustments for: |  |  |  |  |  |
Amortization of net loss |  | (1,765) |  |  | (1,494) |  |  | (1,237) |
Amortization of prior service cost |  | 1,375 |  |  | 1,548 |  |  | 1,665 |
Adjustment for deferred tax effects |  | (57) |  |  | (945) |  |  | (2,059) |
Adjustment due to the effects of regulation |  | (172) |  |  | (2,725) |  |  | (5,941) |
Other comprehensive income related to postretirement benefit plans |  | $ | — |  |  | $ | — |  |  | $ | — |
The following table summarizes the expected future benefit payments of the postretirement benefit plan (in thousands of dollars):
|  | 2026 |  | 2027 |  | 2028 |  | 2029 |  | 2030 |  | 2031-2035
Expected benefit payments |  | $ | 4,855 |  |  | $ | 4,715 |  |  | $ | 4,620 |  |  | $ | 4,580 |  |  | $ | 4,511 |  |  | $ | 21,157 |
Plan Assumptions The following table sets forth the weighted-average assumptions used at the end of each year to determine benefit obligations for all Idaho Power-sponsored pension and postretirement benefits plans:
|  | Pension Plan |  | SMSP |  | Postretirement Benefits
|  | 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024
Discount rate |  | 5.75 | % |  | 5.70 | % |  | 5.65 | % |  | 5.70 | % |  | 5.60 | % |  | 5.70 | %
Rate of compensation increase(1) |  | 4.42 | % |  | 4.43 | % |  | 4.75 | % |  | 4.75 | % |  | — |  |  | — |
Medical trend rate |  | — |  |  | — |  |  | — |  |  | — |  |  | 7.0 | % |  | 6.3 | %
Dental trend rate |  | — |  |  | — |  |  | — |  |  | — |  |  | 4.0 | % |  | 3.5 | %
Measurement date |  | 12/31/2025 |  | 12/31/2024 |  | 12/31/2025 |  | 12/31/2024 |  | 12/31/2025 |  | 12/31/2024
(1) The 2025 rate of compensation increase assumption for the pension plan includes an inflation component of 2.40% plus a 2.02% composite merit increase component that is based on employees' years of service. Merit salary increases are assumed to be 10.6% for employees in their first year of service and scale down to 3.4% for employees in their fortieth year of service and beyond. The following table sets forth the weighted-average assumptions used to determine net periodic benefit cost for all Idaho Power-sponsored pension and postretirement benefit plans:
|  | Pension Plan |  | SMSP |  | Postretirement Benefits
|  | 2025 |  | 2024 |  | 2023 |  | 2025 |  | 2024 |  | 2023 |  | 2025 |  | 2024 |  | 2023
Discount rate |  | 5.70 | % |  | 5.10 | % |  | 5.45 | % |  | 5.70 | % |  | 5.20 | % |  | 5.50 | % |  | 5.70 | % |  | 5.15 | % |  | 5.45 | %
Expected long-term rate of return on assets |  | 7.40 | % |  | 7.40 | % |  | 7.40 | % |  | — |  |  | — |  |  | — |  |  | 6.00 | % |  | 6.00 | % |  | 6.00 | %
Rate of compensation increase |  | 4.42 | % |  | 4.43 | % |  | 4.49 | % |  | 4.75 | % |  | 4.75 | % |  | 4.75 | % |  | — |  |  | — | % |  | — | %
Medical trend rate |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 6.2 | % |  | 7.1 | % |  | 6.7 | %
Dental trend rate |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 4.0 | % |  | 3.5 | % |  | 3.5 | %
The assumed health care cost trend rate used to measure the expected cost of health benefits covered by the postretirement plan was 6.2 percent in 2025 and is assumed to increase to 7.0 percent in 2026, decrease to 6.2 percent in 2027, decrease to 5.5 percent in 2028, and to gradually decrease to 3.8 percent by 2074. For 2025 and beyond, the assumed dental cost trend rate used to measure the expected cost of dental benefits covered by the plan was 4.0 percent, or equal to the medical trend rate if lower. Plan Assets Pension Asset Allocation Policy: The target allocation and actual allocations at December 31, 2025, for the pension asset portfolio by asset class is set forth below:
Asset Class |  | Target Allocation |  | Actual Allocation December 31, 2025
Debt securities |  | 25 | % |  | 25 | %
Equity securities |  | 56 | % |  | 59 | %
Real estate |  | 8 | % |  | 8 | %
Other plan assets |  | 11 | % |  | 8 | %
Total |  | 100 | % |  | 100 | %
Assets are rebalanced as necessary to keep the portfolio close to target allocations. The plan’s principal investment objective is to maximize total return (defined as the sum of realized interest and dividend income and realized and unrealized gain or loss in market price) consistent with prudent parameters of risk and the liability profile of the portfolio. Emphasis is placed on preservation and growth of capital along with adequacy of cash flow sufficient to fund current and future payments to plan participants. The three major goals in Idaho Power’s asset allocation process are to: •determine if the investments have the potential to earn the rate of return assumed in the actuarial liability calculations; •match the cash flow needs of the plan. Idaho Power sets debt security allocations sufficient to cover approximately five years of benefit payments. Idaho Power then utilizes growth instruments (equities, real estate, venture capital) to fund the longer-term liabilities of the plan; and •maintain a prudent risk profile consistent with ERISA fiduciary standards. Allowable plan investments include stocks and stock funds, investment-grade bonds and bond funds, private real estate funds, private infrastructure funds, private direct lending funds, private equity funds, and cash and cash equivalents. With the exception of private real estate holdings, private infrastructure holdings, private direct lending loans, and private equity, investments must be readily marketable so that an entire holding can be disposed of quickly with only a minor effect upon market price. Rate-of-return projections for plan assets are based on historical risk/return relationships among asset classes. The primary measure is the historical risk premium each asset class has delivered versus the yield on the Moody's AA Corporate Bond Index. This historical risk premium is then added to the current yield on the Moody's AA Corporate Bond Index. Additional analysis is performed to measure the expected range of returns, as well as worst-case and best-case scenarios. Based on the current interest rate environment, current rate-of-return expectations are lower than the nominal returns generated over the past 30 years when interest rates were generally higher. Idaho Power’s asset modeling process also utilizes historical market returns to measure the portfolio’s exposure to a “worst-case” market scenario, to determine how much performance could vary from the expected “average” performance over various time periods. This “worst-case” modeling, in addition to cash flow matching and diversification by asset class and investment style, provides the basis for managing the risk associated with investing portfolio assets. Fair Value of Plan Assets: Idaho Power classifies its pension plan and postretirement benefit plan investments using the three-level fair value hierarchy described in Note 17 - "Fair Value Measurements." The following table presents the fair value of the plans' investments by asset category (in thousands of dollars).
|  | Level 1 |  | Level 2 |  | Level 3 |  | Total
Assets at December 31, 2025 |  |  |  |  |  |  |  |
Cash and cash equivalents |  | $ | 11,625 |  |  | $ | — |  |  | $ | — |  |  | $ | 11,625 |
Intermediate bonds |  | 42,326 |  |  | 204,129 |  |  | — |  |  | 246,455 |
Equity Securities: Large-Cap |  | 54,168 |  |  | — |  |  | — |  |  | 54,168 |
Equity Securities: Mid-Cap |  | 106,437 |  |  | — |  |  | — |  |  | 106,437 |
Equity Securities: Small-Cap |  | 85,047 |  |  | — |  |  | — |  |  | 85,047 |
Equity Securities: Micro-Cap |  | 43,752 |  |  | — |  |  | — |  |  | 43,752 |
Equity Securities: Global and International |  | 63,998 |  |  | — |  |  | — |  |  | 63,998 |
Equity Securities: Emerging Markets |  | 3,433 |  |  | — |  |  | — |  |  | 3,433 |
Plan assets measured at NAV (not subject to hierarchy disclosure) |  |  |  |  |  |  |  |
Commingled Fund: Equity Securities: Large-Cap |  |  |  |  |  |  |  | 52,830 |
Commingled Fund: Equity Securities: Global and International |  |  |  |  |  |  |  | 146,047 |
Commingled Fund: Equity Securities: Emerging Markets |  |  |  |  |  |  |  | 52,305 |
Direct Lending Fund: Fixed Income |  |  |  |  |  |  |  | 8,377 |
Real estate |  |  |  |  |  |  |  | 77,141 |
Other Private market investments |  |  |  |  |  |  |  | 71,760 |
Total |  | $ | 410,786 |  |  | $ | 204,129 |  |  | $ | — |  |  | $ | 1,023,375 |
Postretirement plan assets(1) |  | $ | 1,224 |  |  | $ | 30,307 |  |  | $ | — |  |  | $ | 31,531 |
|  | Level 1 |  | Level 2 |  | Level 3 |  | Total
Assets at December 31, 2024 |  |  |  |  |  |  |  |
Cash and cash equivalents |  | $ | 24,946 |  |  | $ | — |  |  | $ | — |  |  | $ | 24,946 |
Intermediate bonds |  | 40,177 |  |  | 184,528 |  |  | — |  |  | 224,705 |
Equity Securities: Large-Cap |  | 49,848 |  |  | — |  |  | — |  |  | 49,848 |
Equity Securities: Mid-Cap |  | 103,117 |  |  | — |  |  | — |  |  | 103,117 |
Equity Securities: Small-Cap |  | 82,932 |  |  | — |  |  | — |  |  | 82,932 |
Equity Securities: Micro-Cap |  | 38,871 |  |  | — |  |  | — |  |  | 38,871 |
Equity Securities: Global and International |  | 58,767 |  |  | — |  |  | — |  |  | 58,767 |
Equity Securities: Emerging Markets |  | 6,093 |  |  | — |  |  | — |  |  | 6,093 |
Plan assets measured at NAV (not subject to hierarchy disclosure) |  |  |  |  |  |  |  |
Commingled Fund: Equity Securities: Large-Cap |  |  |  |  |  |  |  | 54,346 |
Commingled Fund: Equity Securities: Global and International |  |  |  |  |  |  |  | 124,559 |
Commingled Fund: Equity Securities: Emerging Markets |  |  |  |  |  |  |  | 41,590 |
Direct Lending Fund: Fixed Income |  |  |  |  |  |  |  | 5,479 |
Real estate |  |  |  |  |  |  |  | 72,913 |
Other Private market investments |  |  |  |  |  |  |  | 62,976 |
Total |  | $ | 404,751 |  |  | $ | 184,528 |  |  | $ | — |  |  | $ | 951,142 |
Postretirement plan assets(1) |  | $ | 3,054 |  |  | $ | 28,074 |  |  | $ | — |  |  | $ | 31,128 |
(1) The postretirement benefits assets are primarily life insurance contracts. For the years ended December 31, 2025 and 2024, there were no material transfers into or out of Levels 1, 2, or 3. Fair Value Measurement of Level 2 Plan assets and Plan assets measured at NAV: Level 2 Bonds: These investments represent United States government, agency bonds, and corporate bonds. The United States government and agency bonds, as well as the corporate bonds, are not traded on an exchange and are valued utilizing market prices for similar assets or liabilities in active markets. Level 2 Postretirement Asset: This asset represents an investment in a life insurance contract and is recorded at fair value, which is the cash surrender value, less any unpaid expenses. The cash surrender value of this insurance contract is contractually equal to the insurance contract's proportionate share of the market value of an associated investment account held by the insurer. The investments held by the insurer's investment account are all instruments traded on exchanges with readily determinable market prices. Commingled Funds: These funds, made up of global, international and emerging markets equity securities are measured at NAV, are not publicly traded, and therefore no publicly quoted market price is readily available. The values of the commingled funds are presented at estimated fair value, which is determined based on the unit value of the fund. The values of these investments are calculated by the custodian for the fund company on a monthly or more frequent basis, and are based on market prices of the assets held by each of the commingled funds divided by the number of fund shares outstanding for the respective fund. The investments in commingled funds have redemption limitations that permit monthly redemption following notice requirements of 1 to 15 days. Direct Lending Funds: Direct lending strategies are closed-end funds that provide senior secured loans primarily to private, non-investment-grade companies. Direct lending fund investments are valued by the fund companies, or an independent external advisor, based on the estimated fair value of the underlying loans divided by the fund shares outstanding. These direct lending funds also furnish annual audited financial statements that are used to further validate the information provided. These closed-end funds are formed with a stated life of 6 to 10 years, which can be further extended with the approval of the limited partners. There are generally no redemption rights associated with these funds. The limited partner must hold the fund for the life of the fund or find a third-party buyer. Real Estate: Real estate holdings represent investments in open-end and closed-end commingled real estate funds. As the property interests held in these real estate funds are not frequently traded, establishing the market value of the property interests held by the fund, and the resulting unit value of fund shareholders, is based on unobservable inputs including property appraisals by the fund companies, property appraisals by independent appraisal firms, analysis of the replacement cost of the property, discounted cash flows generated by property rents and changes in property values, and comparisons with sale prices of similar properties in similar markets. These real estate funds also furnish annual audited financial statements that are also used to further validate the information provided. Redemptions on the open-end funds are generally available on a quarterly basis, with 10 to 35 days written notice, depending on the individual fund. If the fund has sufficient liquidity, the redemption will be processed at the fund NAV or the fund’s estimate of fair value at the end of the quarter. If the fund does not have sufficient liquidity to honor the full redemption, the remainder will be set for redemption the following quarter on a pro-rata basis with other redemption requests. This same process will repeat until the redemption request has been completed. To protect other fund holders, real estate funds have no duty to liquidate or encumber funds to meet redemption requests. The closed-end funds are formed for a stated life of 7 to 10 years. The fund can be further extended with the approval of the limited partners. There are generally no redemption rights associated with these funds. The limited partner must hold the fund for the life of the fund or find a third-party buyer. Other Private Market Investments: Private market investments represent three categories: venture capital funds, private infrastructure funds, and fund of hedge funds. These funds are valued by the fund companies based on the estimated fair values of the underlying fund holdings divided by the fund shares outstanding or multiplied by the ownership percentages of the holder. Venture capital fund investments are valued by the fund companies based on estimated fair value of the underlying fund holdings divided by the fund shares outstanding. Some venture capital investments have progressed to the point that they have readily available exchange-based market valuations. Early stage venture investments are valued based on unobservable inputs including cost, operating results, discounted cash flows, the price of recent funding events, or pending offers from other viable entities. These private market investments furnish annual audited financial statements that are also used to further validate the information provided. These funds are formed for a stated life of 10 to 15 years. The general partner can extend the fund life for 2 or 3 one-year periods. The fund can be further extended with the approval of the limited partners. There are generally no redemption rights associated with these funds. The limited partner must hold the fund for the life of the fund or find a third-party buyer. The private infrastructure fund investment is valued by the fund manager through a process involving an independent third-party external valuator on a quarterly basis, with each investment undergoing a full independent valuation at least once per year. Redemption on the infrastructure fund are available on a quarterly basis beginning in April of 2027 with 90 days written notice. If the fund has sufficient liquidity, the redemption will be processed at the fund NAV at the end of the quarter. If the fund does not have sufficient liquidity to honor the full redemption, the remainder will be set for redemption the following quarter on a pro-rata basis with other redemption requests. This same process will repeat until the redemption request has been completed. The value of the fund of hedge funds investment is the residual value of an immaterial non-liquid position in a single fund of hedge funds. Employee Savings Plan Idaho Power has a defined contribution plan designed to comply with Section 401(k) of the Internal Revenue Code and that covers substantially all employees. Idaho Power matches specified percentages of employee contributions to the plan. Matching annual contributions were approximately $10.9 million, $10.4 million, and $9.8 million in 2025, 2024, and 2023, respectively. Post-employment Benefits Idaho Power provides certain benefits to former or inactive employees, their beneficiaries, and covered dependents after employment but before retirement, in addition to the health care benefits required under the Consolidated Omnibus Budget Reconciliation Act. These benefits include salary continuation, health care and life insurance for those employees found to be disabled under Idaho Power’s disability plans, and health care for surviving spouses and dependents. Idaho Power accrues a liability for such benefits. The post-employment benefits included in other liabilities on both IDACORP’s and Idaho Power’s consolidated balance sheets at December 31, 2025 and 2024, were approximately $1 million and $3 million.

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