Chelsea is a city in Shelby County, Alabama, United States. It is part of the Birmingham metropolitan area. Chelsea was incorporated on March 1, 1996, with a population of 906. At the 2020 census, the population was 14,982. According to the U.S. Census Bureau, the 2010 population for Chelsea was 10,183 and 14,126 in 2019.

Shelby County is located in the central portion of the U.S. state of Alabama. As of the 2020 census the population was 223,024, making it the sixth-most populous county in Alabama. The county seat is Columbiana. Its largest city is Alabaster. The county is named in honor of Isaac Shelby, Governor of Kentucky from 1792 to 1796 and again from 1812 to 1816. Shelby County is included in the Birmingham–Hoover, AL Metropolitan Statistical Area.