Connecticut Counties by Population (2025)

There are 9 counties in Connecticut.

Capitol Planning Region is the largest county in the state, with a population of 999,690. The most recent census shows that its population has increased by 0.04% since the previous census.

A number of other Connecticut counties also boast relatively large populations for their state, though not able to match the density of Capitol Planning Region:

• Western CT Planning Region : 643,825
• South Central CT Planning Region : 580,517

Connecticut Counties with the Fewest Residents

The smallest county in Connecticut is Northeastern CT Planning Region , with a population of just 98,568. This total represents a increase of 0.0% since the last census count was performed.

Other small counties include:

• Northwest Hills Planning Region : 114,664
• Lower CT River Valley Planning Region : 178,406
• Southeastern CT Planning Region : 284,582

Connecticut Counties with Rapid Growth

Greater Bridgeport Planning Region , with its sizeable population of 340,032, has shown the largest population growth, with an increase of 0.0% since the last census.

Western CT Planning Region has also had relatively high population growth of 0.04% with 643,825 residents.