Columbia Gas of Ohio delivers clean, affordable and efficient natural gas to approximately 1.5 million customers across the state. With headquarters in Columbus, Ohio, it is the largest natural gas utility in Ohio and one of NiSource’s six regulated utility companies. NiSource (NYSE: NI) is one of the largest fully-regulated utility companies in the United States, serving nearly 4 million customers across six states through its local Columbia Gas and NIPSCO brands.