| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Warren | 1 | 38,190 | 39,124 | -0.36% | 2,393 | 16 | City |
| Niles | 2 | 18,065 | 18,416 | -0.28% | 2,101 | 9 | City |
| Girard | 3 | 9,349 | 9,572 | -0.37% | 1,657 | 6 | City |
| Hubbard | 4 | 7,512 | 7,622 | -0.21% | 1,864 | 4 | City |
| Cortland | 5 | 7,007 | 7,097 | -0.24% | 1,618 | 4 | City |
| Newton Falls | 6 | 4,494 | 4,558 | -0.22% | 1,521 | 3 | Village |
| West Farmington | 7 | 528 | 537 | -0.38% | 585 | 1 | Village |
| Orangeville | 8 | 169 | 175 | -0.59% | 227 | 1 | Village |
| Yankee Lake | 9 | 73 | 75 | -1.35% | 130 | 1 | Village |
Warren is the largest city in Trumbull County, with a population of 38,190.
Yankee Lake is the smallest city in Trumbull County, with a population of 73.
There are 9 cities in Trumbull County, Ohio.