NiSource(NI) - 2025 Q4 - Annual Results

Exhibit 99.1 FOR IMMEDIATE RELEASE February 11, 2026 FOR ADDITIONAL INFORMATION Media Investors media@nisource.com investors@nisource.com NiSource announces full-year 2025 results MERRILLVILLE, Ind. - NiSource Inc. (NYSE: NI) today announced, on a GAAP basis, net income available to common shareholders for the year ended December 31, 2025 of $929.5 million, or $1.95 of earnings per diluted share, compared to net income available to common shareholders of $739.7 million, or $1.62 of earnings per diluted shar ...