22 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Gilead | 1 | 6,047 | 5,937 | 0.48% | 177 | 34 | Township |
| Lexington | 2 | 4,828 | 4,848 | -0.08% | 1,186 | 4 | Village |
| Mount Gilead | 3 | 3,554 | 3,499 | 0.31% | 1,049 | 3 | Village |
| Cardington | 4 | 3,331 | 3,067 | 3.54% | 140 | 24 | Township |
| Bennington | 5 | 3,319 | 3,278 | 0.39% | 132 | 25 | Township |
| Fulton | 6 | 3,185 | 3,141 | 0.92% | 111 | 29 | Township |
| Congress | 7 | 2,984 | 2,938 | 0.51% | 95 | 31 | Township |
| Harmony | 8 | 2,634 | 2,600 | 0.42% | 110 | 24 | Township |
| Cardington | 9 | 2,233 | 2,081 | 1.36% | 1,113 | 2 | Village |
| Lincoln | 10 | 2,145 | 2,012 | 1.18% | 94 | 23 | Township |
| South Bloomfield | 11 | 1,897 | 1,777 | 1.44% | 73 | 26 | Township |
| Peru | 12 | 1,528 | 1,505 | 0.53% | 65 | 23 | Township |
| Westfield | 13 | 1,421 | 1,240 | 2.6% | 53 | 27 | Township |
| Washington | 14 | 1,257 | 1,242 | 0.4% | 57 | 22 | Township |
| Candlewood Lake | 15 | 1,189 | 783 | 0.17% | 515 | 2 | CDP |
| Canaan | 16 | 915 | 906 | 0.44% | 33 | 27 | Township |
| Iberia | 17 | 500 | 624 | 0.81% | 130 | 4 | CDP |
| Edison | 18 | 448 | 420 | 1.13% | 1,561 | 0 | Village |
| Marengo | 19 | 281 | 280 | 0% | 1,673 | 0 | Village |
| Fulton | 20 | 251 | 248 | 0% | 1,530 | 0 | Village |
| Chesterville | 21 | 201 | 194 | 0.5% | 980 | 0 | Village |
| Sparta | 22 | 123 | 122 | 0% | 1,414 | 0 | Village |
Gilead is the largest city in Morrow County, with a population of 6,047.
Sparta is the smallest city in Morrow County, with a population of 123.
There are 22 cities in Morrow County, Ohio.