Identifiers: city · borough · CDP
| Rank | Community | Population |
|---|---|---|
| 1 | Waterbury (city), CT | 114,403 |
| 2 | New Britain (city), CT | 74,135 |
| 3 | Meriden (city), CT | 60,850 |
| 4 | Bristol (city), CT | 60,833 |
| 5 | Middletown (city), CT | 47,717 |
| 6 | Naugatuck (borough), CT | 31,519 |
| 7 | Newington (CDP), CT | 30,536 |
| 8 | North Haven (CDP), CT | 24,253 |
| 9 | Ansonia (city), CT | 18,918 |
| 10 | Wallingford Center (CDP), CT | 18,278 |
| 11 | Derby (city), CT | 12,325 |
| 12 | Kensington (CDP), CT | 9,962 |
| 13 | Oakville (CDP), CT | 9,504 |
| 14 | Sandy Hook (CDP), CT | 9,114 |
| 15 | Cheshire Village (CDP), CT | 6,499 |
| 16 | Terryville (CDP), CT | 5,202 |
| 17 | Heritage Village (CDP), CT | 5,091 |
| 18 | Watertown (CDP), CT | 3,938 |
| 19 | Quinnipiac University (CDP), CT | 3,639 |
| 20 | Northwest Harwinton (CDP), CT | 3,158 |