Farmington is a city in Van Buren County, Iowa, United States. The population was 579 at the time of the 2020 census. Farmington was l…Farmington is a city in Van Buren County, Iowa, United States. The population was 579 at the time of the 2020 census. Farmington was laid out in 1839. It was named after Farmington, Connecticut. The town was incorporated on January 11, 1841.