Company: AILIM
Filing Date: 2025-05-05
Form Type: 10-Q
Source: 0001002910-25-000098
Chunk: 90

Company: Ameren Illinois Co
Filing Date: 2025-05-05
Form: 10-Q
Item: Part I, Item 1
Chunk 90
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$(20)(a)Service cost, net of capitalization, is reflected in “Operating Expenses – Other operations and maintenance” on Ameren’s statement of income.(b)Prior service cost (credit) is amortized on a straight-line basis over the average future service of active participants benefiting under a plan amendment. Net actuarial gains or losses related to the net benefit obligation subject to amortization are amortized on a straight-line basis over 10 years. The difference between the actual and expected return on plan assets is amortized over 4 years.(c)Non-service cost components are reflected in “Other Income, Net” on Ameren’s consolidated statement of income. See Note 5 – Other Income, Net for additional information.(d)Does not include the impact of the tracker for the difference between the level of pension and postretirement benefit costs (income) incurred by Ameren Missouri under GAAP and the level of such costs included in customer rates.Ameren Missouri and Ameren Illinois are responsible for their respective share of Ameren’s pension and other postretirement costs. The following table presents the respective share of net periodic pension and other postretirement benefit costs (income) incurred for the three months ended March 31, 2025 and 2024:Pension BenefitsPostretirement BenefitsThree MonthsThree Months2025202420252024Ameren Missouri(a)$(4)$(12)$(7)$(7)Ameren Illinois(2)(9)(13)(13)Other(1)(2)— — Ameren(a)$(7)$(23)$(20)$(20)(a)Does not include the impact of the tracker for the difference between the level of pension and postretirement benefit costs (income) incurred by Ameren Missouri under GAAP and the level of such costs included in customer rates.

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NOTE 12 – INCOME TAXES

The following table presents a reconciliation of the federal statutory corporate income tax rate to the effective income tax rate for the three months ended March 31, 2025 and 2024:AmerenAmeren MissouriAmeren Illinois202520242025202420252024Three MonthsFederal statutory corporate income tax rate21 %21 %21 %21 %21 %21 %Increases (decreases) from:Amortization of excess deferred taxes(a)(7)(8)(8)(12)(3)(4)Amortization of deferred investment tax credit(1