FOR ADDITIONAL INFORMATION (Form 8-K)

FOR ADDITIONAL INFORMATION

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NiSource announces second quarter results

•2025 non-GAAP adjusted EPS guidance narrowed to upper half of range

•Reaffirming expected annual 6%-8% 2025-2029 non-GAAP adjusted EPS growth

MERRILLVILLE, Ind. - NiSource Inc. (NYSE: NI) today announced, on a GAAP basis, net income available to common shareholders for the three months ended June 30, 2025, of $102.2 million, or $0.22 of earnings per diluted share, compared to net income available to common shareholders of $85.8 million, or $0.19 of earnings per diluted share, for the same period of 2024. For the six months ended June 30, 2025, on a GAAP basis NiSource's net income available to common shareholders was $577.0 million, or $1.22 diluted earnings per share, compare to net income available to common shareholders of $430.1 million, or $0.95 diluted earnings per share, for the same period of 2024.

NiSource also reported second quarter 2025 non-GAAP adjusted net income available to common shareholders of $101.9 million, or $0.22 of adjusted earnings per share ("EPS") compared to non-GAAP adjusted net income available to common shareholders of $94.7 million, or $0.21 of adjusted EPS, for the same period of 2024. For the six months ended June 30, 2025, NiSource's non-GAAP adjusted net income available to common shareholders of $564.2 million, or $1.19 adjusted EPS, compared to non-GAAP adjusted net income available to common shareholders of $477.5 million, or $1.06 adjusted EPS, for the same period of 2024. Schedule 1 of this press release contains a complete reconciliation of GAAP measures to non-GAAP measures. **

NiSource is narrowing 2025 non-GAAP adjusted EPS guidance to the upper half of $1.85-$1.89. Annual rate base growth of 8%-10% and non-GAAP adjusted EPS growth of 6%-8% annually is driven by $19.4 billion of capital expenditures for the 2025-2029 period.

"Our dedicated team of employees and contractors work hard to serve our customers and communities every day. As we look ahead, we remain focused on strong execution of our strategy and operations," said NiSource President and CEO, Lloyd Yates. "Our base capital plan includes critical investments to ensure reliability for our customers and the increased 2025 earnings expectations is driven by our dedication and ability to deliver on our financial commitments while supporting the growth and reliability of our systems."

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**Non-GAAP Disclosure Statement