40 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Warren | 1 | 38,442 | 39,164 | -0.31% | 2,409 | 16 | City |
| Weathersfield | 2 | 24,400 | 24,596 | -0.04% | 1,115 | 22 | Township |
| Liberty | 3 | 21,301 | 21,501 | -0.06% | 940 | 23 | Township |
| Howland | 4 | 18,947 | 19,041 | 0.03% | 1,075 | 18 | Township |
| Niles | 5 | 18,147 | 18,419 | -0.25% | 2,110 | 9 | City |
| Hubbard | 6 | 12,840 | 12,934 | -0.02% | 528 | 24 | Township |
| Girard | 7 | 9,394 | 9,574 | -0.32% | 1,665 | 6 | City |
| Champion | 8 | 9,326 | 9,378 | 0.02% | 359 | 26 | Township |
| Newton | 9 | 8,554 | 8,605 | 0% | 352 | 24 | Township |
| Brookfield | 10 | 8,396 | 8,431 | 0.01% | 343 | 24 | Township |
| Hubbard | 11 | 7,538 | 7,619 | -0.17% | 1,871 | 4 | City |
| Cortland | 12 | 7,056 | 7,095 | -0.08% | 1,630 | 4 | City |
| Bazetta | 13 | 5,886 | 5,903 | 0.05% | 282 | 21 | Township |
| Warren | 14 | 5,547 | 5,745 | -0.45% | 159 | 35 | Township |
| Warren | 15 | 4,678 | 4,690 | 0.04% | 322 | 15 | Township |
| Newton Falls | 16 | 4,520 | 4,567 | -0.18% | 1,530 | 3 | Village |
| Vienna | 17 | 4,063 | 4,061 | 0.1% | 173 | 23 | Township |
| Warren | 18 | 3,816 | 3,932 | -0.34% | 102 | 37 | Township |
| Southington | 19 | 3,738 | 3,726 | 0.13% | 141 | 27 | Township |
| Warren | 20 | 3,706 | 3,834 | -0.35% | 161 | 23 | Township |
| Mesopotamia | 21 | 3,402 | 3,417 | 0% | 128 | 27 | Township |
| Farmington | 22 | 2,947 | 2,964 | 0% | 108 | 27 | Township |
| Bristol | 23 | 2,685 | 2,701 | 0% | 103 | 26 | Township |
| Braceville | 24 | 2,456 | 2,458 | 0.08% | 106 | 23 | Township |
| Fowler | 25 | 2,345 | 2,352 | 0% | 92 | 26 | Township |
| Mecca | 26 | 2,322 | 2,321 | 0.09% | 114 | 20 | Township |
| North Bloomfield | 27 | 1,877 | 1,840 | 0.48% | 63 | 30 | Township |
| Hartford | 28 | 1,848 | 1,858 | 0.05% | 70 | 27 | Township |
| Johnston | 29 | 1,736 | 1,735 | 0.12% | 70 | 25 | Township |
| Kinsman | 30 | 1,715 | 1,726 | 0% | 66 | 26 | Township |
| Hartford | 31 | 1,485 | 1,435 | 0.47% | 54 | 28 | Township |
| Vernon | 32 | 1,343 | 1,344 | 0% | 57 | 24 | Township |
| Bloomfield | 33 | 1,234 | 1,240 | 0.08% | 48 | 25 | Township |
| Warren | 34 | 1,041 | 1,086 | -0.76% | 48 | 22 | Township |
| Greene | 35 | 952 | 947 | 0.32% | 40 | 24 | Township |
| Gustavus | 36 | 824 | 829 | 0% | 33 | 25 | Township |
| West Farmington | 37 | 532 | 538 | -0.19% | 589 | 1 | Village |
| Orangeville | 38 | 168 | 174 | -0.59% | 226 | 1 | Village |
| Brookfield | 39 | 105 | 99 | 0.96% | 4 | 30 | Township |
| Yankee Lake | 40 | 72 | 74 | 0% | 128 | 1 | Village |
Warren is the largest city in Trumbull County, with a population of 38,442.
Yankee Lake is the smallest city in Trumbull County, with a population of 72.
There are 40 cities in Trumbull County, Ohio.