Columbia is a census-designated place in Howard County, Maryland, United States. It is a planned community consisting of 10 self-contained villages. The census-designated place had a population of 104,681 at the 2020 census, making it the second most populous community in Maryland after Baltimore. Columbia, located between Baltimore and Washington, D.C., is officially part of the Baltimore metropolitan area.

Howard County is located in the U.S. state of Maryland. As of the 2020 census, the population was 334,529. Since there are no incorporated municipalities, there is no incorporated county seat either. Therefore, its county seat is the unincorporated community of Ellicott City. Howard County is included in the Baltimore-Columbia-Towson, MD Metropolitan Statistical Area, which is part of the larger Washington–Baltimore combined statistical area.