Howard County is a county 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 part of the larger Washington–Baltimore combined statistic…Howard County is a county 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 part of the larger Washington–Baltimore combined statistical area. The county is part of the Central Maryland region of the state.