- Taylorville (Population: 11,427)
- Teutopolis (Population: 1,559)
- Third Lake (Population: 1,355)
- Thomasboro (Population: 1,233)
- Thornton (Population: 2,582)
- Tilton (Population: 2,976)
- Tinley Park (Population: 48,401)
- Toledo (Population: 1,166)
- Tolono (Population: 2,700)
- Toluca (Population: 1,339)
- Toulon (Population: 1,400)
- Tower Lakes (Population: 1,310)
- Tremont (Population: 2,029)
- Trenton (Population: 2,610)
- Troy (Population: 8,524)
- Tuscola (Population: 4,448)
