List of counties in Connecticut

This is a list of counties in Connecticut. There are currently eight counties in the U.S. state of Connecticut. Four of them were created in 1666, shortly after the Connecticut Colony and the New Haven Colony combined. Two additional counties were created later in the colonial era, and two more counties, Middlesex and Tolland, were created after American independence (both in 1785). Six of the counties are named for locations in England, where many early Connecticut settlers originated.

Although Connecticut is divided into counties, there is no county government in Connecticut and local government consists of cities and towns. County government was abolished in Connecticut in 1960, although the names remain for geographical purposes. Counties are, however, still used by the state to organize its judicial and state marshal system. Connecticut's court jurisdictions still adhere to the county boundaries, except for Fairfield, Hartford and New Haven, which have been further subdivided into several jurisdictions.

The FIPS county code is the five-digit Federal Information Processing Standard (FIPS) code which uniquely identifies counties and county equivalents in the United States. The three-digit number is unique to each individual county within a state, but to be unique within the entire United States, it must be prefixed by the state code. This means that, for example, while Fairfield County, Connecticut is 001, Belknap County, New Hampshire and Alachua County, Florida are also 001. To uniquely identify Fairfield County, Connecticut, one must use the state code of 09 plus the county code of 001; therefore, the unique nationwide identifier for Fairfield County, Connecticut is 09001. The links in the column FIPS County Code are to the Census Bureau Info page for that county.