Data / Rankings / Population / Counties in Connecticut

Counties in Connecticut by population

Capitol Planning Region had the highest population of 9 counties in 2023, at 981,775. Northeastern Connecticut Planning Region had the lowest, at 96,790. The median was 332,081 and the figure for Connecticut was 3.64 million. Source: the U.S. Census Bureau.

Highest981,775Capitol Planning Region
Lowest96,790Northeastern Connecticut Planning Region
Median332,0819 counties
Connecticut3,641,369History

All counties, 2023

CSVChart (SVG)

Capitol Planning RegionCapitol Planning Region: 981,775 persons981,775Western Connecticut Planning Regi…Western Connecticut Planning Region: 630,270 persons630,270South Central Connecticut Plannin…South Central Connecticut Planning Region: 572,366 persons572,366Naugatuck Valley Planning RegionNaugatuck Valley Planning Region: 457,384 persons457,384Greater Bridgeport Planning RegionGreater Bridgeport Planning Region: 332,081 persons332,081Southeastern Connecticut Planning…Southeastern Connecticut Planning Region: 280,776 persons280,776Lower Connecticut River Valley Pl…Lower Connecticut River Valley Planning Region: 176,419 persons176,419Northwest Hills Planning RegionNorthwest Hills Planning Region: 113,508 persons113,508Northeastern Connecticut Planning…Northeastern Connecticut Planning Region: 96,790 persons96,790
persons. Source: U.S. Census Bureau. Retrieved 2026-10-08.

Full ranking

RankCounties2023
persons		Change on 2022
1Capitol Planning Region981,775+0.7%
2Western Connecticut Planning Region630,270+0.7%
3South Central Connecticut Planning Region572,366+0.5%
4Naugatuck Valley Planning Region457,384+0.8%
5Greater Bridgeport Planning Region332,081+0.9%
6Southeastern Connecticut Planning Region280,776+0.5%
7Lower Connecticut River Valley Planning Region176,419+0.2%
8Northwest Hills Planning Region113,508+0.2%
9Northeastern Connecticut Planning Region96,790+0.7%

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 981,775 in 2023, according to the U.S. Census Bureau.

Which county has the lowest population?

Northeastern Connecticut Planning Region, with 96,790 in 2023.

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