List of Connecticut counties:

1. Fairfield County: one of four original counties created in Connecticut in 1666. Historic county seats: Bridgeport and Danbury.
2. Hartford County: one of four original counties created in Connecticut in 1666. Historic county seat: Hartford.
3. Litchfield County: formed in 1751 from parts of Fairfield County, Hartford County, and New Haven County. Historic county seats: New Milford and Winsted.
4. Middlesex County: formed in 1785 from parts of Hartford County and New London County. Historic county seat: Middletown.
5. New Haven County: one of four original counties created in Connecticut in 1666. Historic county seats: New Haven and Waterbury.
6. New London County: one of four original counties created in Connecticut in 1666. Historic county seats: New London and Norwich.
7. Tolland County: formed in 1785 from parts of Hartford County, and Windham County. Historic county seat: Tolland.
8. Windham County: formed in 1726 from parts of Hartford County, and New London County. Historic county seats: Putnam and Willimantic.