NISOURCE INC.

13. Income Taxes

Our interim effective tax rates reflect the estimated annual effective tax rates for 2025 and 2024 applied to year-to-date pretax income, adjusted for tax expense associated with certain discrete items. The effective tax rates for the three months ended June 30, 2025 and 2024 were 19.1% and 14.6%, respectively. The effective tax rates for the six months ended June 30, 2025 and 2024 were 17.1% and 15.7%, respectively. These effective tax rates differ from the federal statutory tax rate of 21% primarily due to net income attributable to noncontrolling interest, amortization of excess deferred income taxes, federal tax credits net of deferred regulatory liabilities, state income taxes, and other permanent book-to-tax differences.

The increase in the three month effective tax rate of 4.5% in 2025 compared to 2024 is primarily driven by higher state income taxes and lower AFUDC equity, partially offset by the increase in federal tax credits.

The increase in the six month effective tax rate of 1.4% in 2025 compared to 2024 is primarily driven by higher state income taxes and lower AFUDC equity.

As of June 30, 2025, there have been no material changes to our unrecognized tax benefits or possible changes that could reasonably be expected to occur during the next twelve months. See Note 15 to the Company’s Consolidated Financial Statements in the Annual Report on Form 10-K for the year ended December 31, 2024, for a discussion of these unrecognized tax benefits.