23 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Youngstown | 1 | 58,586 | 59,890 | -0.44% | 1,727 | 33.93 | City |
| Austintown | 2 | 30,577 | 29,467 | 0.2% | 2,632 | 11.62 | CDP |
| Struthers | 3 | 9,836 | 10,035 | -0.4% | 2,701 | 3.64 | City |
| Campbell | 4 | 7,685 | 7,835 | -0.39% | 2,068 | 3.72 | City |
| Canfield | 5 | 7,565 | 7,677 | -0.29% | 1,482 | 5.10 | City |
| Champion Heights | 6 | 6,309 | 6,354 | -0.21% | 754 | 8.37 | CDP |
| Sebring | 7 | 4,107 | 4,177 | -0.34% | 1,646 | 2.50 | Village |
| Lordstown | 8 | 3,319 | 3,323 | -0.03% | 143 | 23.19 | Village |
| McDonald | 9 | 3,104 | 3,166 | -0.39% | 1,827 | 1.70 | Village |
| Poland | 10 | 2,402 | 2,454 | -0.41% | 1,470 | 1.63 | Village |
| Woodworth | 11 | 2,396 | 1,530 | 7.16% | 776 | 3.09 | CDP |
| New Middletown | 12 | 1,477 | 1,501 | -0.34% | 1,692 | 0.87 | Village |
| North Lima | 13 | 1,377 | 1,341 | 7.08% | 201 | 6.86 | CDP |
| Craig Beach | 14 | 1,055 | 1,074 | -0.38% | 1,346 | 0.78 | Village |
| South Canal | 15 | 991 | 901 | -0.7% | 587 | 1.69 | CDP |
| Lowellville | 16 | 980 | 1,000 | -0.41% | 720 | 1.36 | Village |
| Beloit | 17 | 885 | 902 | -0.34% | 908 | 0.97 | Village |
| New Springfield | 18 | 710 | 359 | 7.09% | 449 | 1.58 | CDP |
| Hilltop | 19 | 683 | 639 | 1.49% | 909 | 0.75 | CDP |
| Lake Milton | 20 | 586 | 541 | 7.13% | 394 | 1.49 | CDP |
| Petersburg | 21 | 424 | 472 | 7.07% | 280 | 1.52 | CDP |
| Maplewood Park | 22 | 274 | 283 | 0% | 347 | 0.79 | CDP |
| Damascus | 23 | 138 | 286 | -12.66% | 173 | 0.80 | CDP |
Youngstown is the largest city in Mahoning County, with a population of 58,586.
Damascus is the smallest city in Mahoning County.
There are 23 cities in Mahoning County, Ohio.