The City of Colchester is a local government district with city status in Essex, England, named after its main settlement, Colchester. The district also includes the towns of West Mersea and Wivenhoe and the surrounding rural areas stretching from Dedham Vale on the Suffolk border in the north to Mersea Island in the Colne Estuary in the south.

City status in the United Kingdom is granted by the monarch of the United Kingdom to specific centres of population, which might or might not meet the generally accepted definition of cities. As of 22 November 2022, there are 76 cities in the United Kingdom—55 in England, seven in Wales, eight in Scotland, and six in Northern Ireland. Although it carries no special rights, the status of city can be a marker of prestige and confer local pride.