As of February 2026 NiSource has a market cap of โฌ18.61 Billion. This makes NiSource the world's 1108th most valuable company by market cap according to our data. The market capitalization, commonly called market cap, is the total market value of a publicly traded company's outstanding shares and is commonly used to measure how much a company is worth.
On Feb 24th, 2026 the market cap of NiSource was reported to be: