# Counties in Connecticut by population, 2025

All 9 values come from U.S. Census Bureau for 2025, so the places are comparable.

- Indicator id: `population`
- Unit: persons
- Definition: 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.
- Source: 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
- Citation: 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.
- Web page: https://invokely.ai/rankings/population/connecticut-counties
- CSV: https://invokely.ai/download/rankings/population/connecticut-counties.csv

| Rank | Place | persons |
|---:|---|---:|
| 1 | Capitol Planning Region | 994,115 |
| 2 | Western Connecticut Planning Region | 640,482 |
| 3 | South Central Connecticut Planning Region | 578,741 |
| 4 | Naugatuck Valley Planning Region | 463,349 |
| 5 | Greater Bridgeport Planning Region | 337,697 |
| 6 | Southeastern Connecticut Planning Region | 284,015 |
| 7 | Lower Connecticut River Valley Planning Region | 177,311 |
| 8 | Northwest Hills Planning Region | 114,690 |
| 9 | Northeastern Connecticut Planning Region | 98,096 |