Company: AILIM
Filing Date: 2025-11-06
Form Type: 10-Q
Source: 0001002910-25-000129
Chunk: 151

Company: Ameren Illinois Co
Filing Date: 2025-11-06
Form: 10-Q
Item: Part I, Item 1
Chunk 151
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 with short-term debt of $3 million.

Ameren Illinois Electric Distribution

 Interest charges increased by $3 million and $7 million in the three and nine months ended September 30, 2025, respectively, primarily because of issuances of long-term debt in June 2024 and March 2025, which increased interest expense by $2 million and $12 million, respectively. The increases in the nine months ended September 30, 2025 were partially offset by $2 million due to decreased levels of borrowing on short-term debt and by $2 million due to the maturity of senior secured notes in March 2025.

Ameren Illinois Natural Gas

Interest charges were comparable between periods.

Income Taxes

The following table presents effective income tax rates for the three and nine months ended September 30, 2025 and 2024:

Three Months(a)Nine Months(a)2025202420252024Ameren7 %11 %11 %13 %Ameren Missouri6 %(2)%6 %(1)%Ameren Illinois10 %24 %20 %24 %Ameren Illinois Electric Distribution25 %20 %21 %19 %Ameren Illinois Natural Gas25 %22 %26 %27 %Ameren Illinois Transmission2 %27 %17 %27 %Ameren Transmission(12)%27 %13 %27 %

(a)Estimate of the annual effective income tax rate adjusted to reflect the tax effect of items discrete to the three and nine months ended September 30, 2025 and 2024.

See Note 12 – Income Taxes under Part I, Item 1, of this report for a reconciliation of the federal statutory corporate income tax rate to the effective income tax rate for the Ameren Companies.

65

The effective tax rate was lower at Ameren Transmission and Ameren Illinois Transmission for the three and nine months ended September 30, 2025 compared with the year-ago periods due to a revaluation of excess deferred income tax regulatory liabilities in the third quarter of 2025. In 2024, the IRS issued a series of private letter rulings to another taxpayer, which provided guidance on applying IRS normalization rules to the calculation of tax benefits applicable to the ratemaking treatment related to net operating loss carryforwards. The rulings concluded that, for ratemaking purposes, net operating loss carryforwards should be