Data / Rankings / Population / Counties in Connecticut

Counties in Connecticut by population

Capitol Planning Region had the highest population of 9 counties in 2024, at 989,194. Northeastern Connecticut Planning Region had the lowest, at 97,627. The median was 336,391 and the figure for Connecticut was 3.67 million. Source: the U.S. Census Bureau.

Highest989,194Capitol Planning Region
Lowest97,627Northeastern Connecticut Planning Region
Median336,3919 counties
Connecticut3,674,449History

All counties, 2024

CSVChart (SVG)

Capitol Planning RegionCapitol Planning Region: 989,194 persons989,194Western Connecticut Planning Regi…Western Connecticut Planning Region: 637,721 persons637,721South Central Connecticut Plannin…South Central Connecticut Planning Region: 577,538 persons577,538Naugatuck Valley Planning RegionNaugatuck Valley Planning Region: 461,480 persons461,480Greater Bridgeport Planning RegionGreater Bridgeport Planning Region: 336,391 persons336,391Southeastern Connecticut Planning…Southeastern Connecticut Planning Region: 283,171 persons283,171Lower Connecticut River Valley Pl…Lower Connecticut River Valley Planning Region: 177,047 persons177,047Northwest Hills Planning RegionNorthwest Hills Planning Region: 114,280 persons114,280Northeastern Connecticut Planning…Northeastern Connecticut Planning Region: 97,627 persons97,627
persons. Source: U.S. Census Bureau. Retrieved 2026-10-08.

Full ranking

RankCounties2024
persons		Change on 2023
1Capitol Planning Region989,194+0.8%
2Western Connecticut Planning Region637,721+1.2%
3South Central Connecticut Planning Region577,538+0.9%
4Naugatuck Valley Planning Region461,480+0.9%
5Greater Bridgeport Planning Region336,391+1.3%
6Southeastern Connecticut Planning Region283,171+0.9%
7Lower Connecticut River Valley Planning Region177,047+0.4%
8Northwest Hills Planning Region114,280+0.7%
9Northeastern Connecticut Planning Region97,627+0.9%

Other periods

About this ranking

Resident population. Spain and the EU: 1 January, with Spanish figures from the official municipal register (Padrón). United States: Census Bureau population estimates for 1 July. Other countries and the World: World Bank mid-year estimates, which count all residents regardless of legal status or citizenship.

For Denmark, Statistics Denmark counts the registered resident population on 1 January. Greenland and the Faroe Islands are excluded. The annual series selects the first-quarter reference date from FOLK1A. The World Bank series exists for every country, so use it (through compare) to rank countries on one basis.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-08.

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Questions

Which county has the highest population?

Capitol Planning Region, with 989,194 in 2024, according to the U.S. Census Bureau.

Which county has the lowest population?

Northeastern Connecticut Planning Region, with 97,627 in 2024.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). Retrieved 2026-10-08.

Population: other rankings

Counties in Connecticut: more rankings