17 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Vernon | 1 | 19,310 | 15,700 | 3.33% | 618 | 31 | Township |
| Center | 2 | 8,144 | 8,183 | -0.07% | 325 | 25 | Township |
| North Vernon | 3 | 6,555 | 6,603 | -0.15% | 854 | 8 | City |
| Scipio | 4 | 5,125 | 5,145 | -0.02% | 160 | 32 | Township |
| Vernon | 5 | 3,499 | 3,401 | 1.27% | 81 | 43 | Township |
| Vernon | 6 | 2,869 | 2,876 | -0.03% | 84 | 34 | Township |
| Campbell | 7 | 1,136 | 1,112 | 0.35% | 35 | 32 | Township |
| Lovett | 8 | 1,050 | 1,050 | 0% | 36 | 29 | Township |
| Hayden | 9 | 964 | 542 | 3.21% | 390 | 2 | CDP |
| Columbia | 10 | 891 | 893 | 0.11% | 23 | 39 | Township |
| Sand Creek | 11 | 848 | 851 | 0% | 31 | 28 | Township |
| Bigger | 12 | 650 | 646 | 0% | 21 | 31 | Township |
| Vernon | 13 | 648 | 643 | 0.31% | 19 | 34 | Township |
| Scipio | 14 | 433 | 413 | 0.93% | 33 | 13 | Township |
| Scipio | 15 | 330 | 308 | 3.45% | 287 | 1 | CDP |
| Vernon | 16 | 234 | 234 | 0% | 1,130 | 0 | Town |
| Butlerville | 17 | 154 | 185 | -5.52% | 413 | 0 | CDP |
Vernon is the largest city in Jennings County, with a population of 19,310.
Butlerville is the smallest city in Jennings County, with a population of 154.
There are 17 cities in Jennings County, Indiana.