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 981,848. The most recent census shows that its population has increased by 0.02% 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 : 626,007
• South Central CT Planning Region : 567,670

Connecticut Counties with the Fewest Residents

The smallest county in Connecticut is Northeastern CT Planning Region, with a population of just 97,780. This total represents a increase of 0.0% since the last census count was performed.

Other small counties include:

• Northwest Hills Planning Region : 113,835
• Lower CT River Valley Planning Region : 176,681
• Southeastern CT Planning Region : 280,388

Connecticut Counties with Rapid Growth

Northeastern CT Planning Region, with its current population of 97,780, has shown the largest population growth, with an increase of 0.0% since the last census.

Capitol Planning Region has also had relatively high population growth of 0.02% with 981,848 residents.