As of December 2025 NiSource has a market cap of โฌ16.76 Billion. This makes NiSource the world's 1137th 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 Dec 9th, 2025 the market cap of NiSource was reported to be: