Merrillville is a town located in Ross Township, Lake County, Indiana, within the United States. Situated in east-central Lake County, it is part of the Chicago metropolitan area. As of the 2020 census, the town had a population of 36,444.
The town gained distinction on January 1, 2015, when it became the most populated town in Indiana following the conversion of Fishers in Hamilton County from a town to a city. Additionally, Merrillville serves as a major shopping hub for Northwest Indiana.