Dexter is a city in Washtenaw County in the U.S. state of Michigan. Originally a village, Dexter residents voted to adopt a city charter in November 2014. The population was 4,067 at the 2010 census. Between 2000 and 2010, Dexter's population grew 73.9%, making it one of the fastest growing communities in the state.While there is no formal political connection between the City of Dexter and the adjacent Township of Dexter, both share the 48130 zip code and Dexter, Michigan mailing address, as well as some basic services. The township was named for village founder and Washtenaw county's first circuit judge Samuel William Dexter.