Connecticut's 2nd congressional district is a congressional district in the U.S. state of Connecticut. Located in the eastern part of the state, the district includes all of New London County, Tolland County, and Windham County, along with parts of Hartford, Middlesex, and New Haven counties. Principal cities include Enfield, Norwich, New London, and Groton.

New London County is in the southeastern corner of Connecticut and comprises the Norwich-New London, Connecticut Metropolitan Statistical Area, which is also included in the Hartford-East Hartford, Connecticut Combined Statistical Area. There is no county government and no county seat, as is the case with all eight of Connecticut's counties; towns are responsible for all local government activities, including fire and rescue, snow removal, and schools.