NiSource is a regulated utility holding company serving approximately 3.8 million customers across six states. Its two core businesses are natural gas distribution and electric utility operations. Through its Columbia Gas subsidiaries and NIPSCO Gas, NiSource distributes natural gas to approximately 3.3 million customers in Ohio, Pennsylvania, Virginia, Kentucky, Maryland, and northern Indiana — primarily for space heating, making the business heavily seasonal. Through NIPSCO Electric, NiSource generates, transmits, and distributes electricity to approximately 500,000 customers across northern Indiana. NiSource earns revenue primarily through regulated tariffs approved by state utility commissions, which allow recovery of operating costs plus a regulated return on invested capital. Rate base growth — driven by capital investment in gas and electric infrastructure — is the primary earnings driver. NiSource also uses tracker mechanisms, weather normalization adjustments, and gas cost pass-throughs to reduce earnings volatility. A newer and significant growth initiative is GenCo, a regulated entity established to develop generation assets specifically for large data center customers under commercially negotiated fixed-rate contracts rather than traditional rate cases. In September 2025, NiSource signed a 15-year contract with Amazon under the GenCo framework, under which GenCo will develop approximately $6–7B of new assets, including two 1,300 MW gas turbines and 400 MW of battery storage. Blackstone holds a 19.9% minority stake in GenCo. NiSource's consolidated five-year capital plan totals approximately $28B.