Florida's 3rd congressional district is an electoral district of the United States House of Representatives located in Florida. It presently comprises a large section of north central Florida, including the entire counties of Alachua, Baker, Bradford, Columbia, Dixie Gilchrist, Hamilton, Levy, Suwannee, and Union, along with the majority of Lafayette and Marion County. The city of Gainesville is in the district as well as part of Ocala.

Alachua County is a county in the north central portion of the U.S. state of Florida. As of the 2020 census, the population was 278,468. The county seat is Gainesville, the home of the University of Florida since 1906, when the campus opened with 106 students.