17 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Vernon township | 1 | 20,058 | 15,701 | 5.21% | 642 | 31.22 | Township |
| Center township | 2 | 8,181 | 8,182 | 0.23% | 327 | 25.03 | Township |
| North Vernon | 3 | 6,540 | 6,604 | -0.2% | 852 | 7.67 | City |
| Scipio township | 4 | 5,152 | 5,144 | 0.16% | 161 | 32.07 | Township |
| Vernon township | 5 | 3,427 | 3,401 | 0.56% | 80 | 43.03 | Township |
| Vernon township | 6 | 2,907 | 2,875 | 0.48% | 85 | 34.15 | Township |
| Campbell township | 7 | 1,139 | 1,111 | 0.89% | 36 | 32.06 | Township |
| Lovett township | 8 | 1,059 | 1,052 | 0.38% | 36 | 29.46 | Township |
| Hayden | 9 | 964 | 542 | 3.21% | 390 | 2.47 | CDP |
| Columbia township | 10 | 890 | 893 | 0.11% | 23 | 39.48 | Township |
| Sand Creek township | 11 | 848 | 849 | 0.24% | 31 | 27.72 | Township |
| Bigger township | 12 | 652 | 647 | 0.46% | 21 | 30.69 | Township |
| Vernon township | 13 | 643 | 644 | 0% | 19 | 34.03 | Township |
| Scipio township | 14 | 431 | 414 | 0.7% | 33 | 13.22 | Township |
| Scipio | 15 | 330 | 308 | 3.45% | 287 | 1.15 | CDP |
| Vernon | 16 | 236 | 236 | 0% | 1,140 | 0.21 | Town |
| Butlerville | 17 | 154 | 185 | -5.52% | 413 | 0.37 | CDP |
Vernon township is the largest city in Jennings County, with a population of 20,058.
Butlerville is the smallest city in Jennings County.
There are 17 cities in Jennings County, Indiana.