| City | County | 2026 Pop. ↓ |
|---|---|---|
| Trumbull | Greater Bridgeport Planning Region | 37,999 |
| Torrington | Northwest Hills Planning Region | 35,888 |
| Tolland | Capitol Planning Region | 14,808 |
| Thompson | Northeastern Connecticut Planning Region | 9,647 |
| Thomaston | Naugatuck Valley Planning Region | 7,591 |