14 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Bainbridge | 1 | 17,561 | 17,158 | 0.57% | 500 | 35 | Township |
| Greencastle | 2 | 12,859 | 12,603 | 0.24% | 375 | 34 | Township |
| Greencastle | 3 | 9,951 | 9,819 | 0.22% | 1,909 | 5 | City |
| Floyd | 4 | 4,358 | 4,115 | 0.86% | 129 | 34 | Township |
| Cloverdale | 5 | 4,161 | 3,894 | 0.9% | 91 | 46 | Township |
| Cloverdale | 6 | 2,232 | 2,051 | 1.36% | 640 | 3 | Town |
| Jefferson | 7 | 1,378 | 1,290 | 0.95% | 34 | 41 | Township |
| Jackson | 8 | 917 | 862 | 0.99% | 27 | 35 | Township |
| Roachdale | 9 | 887 | 839 | 0.91% | 1,750 | 1 | Town |
| Russell | 10 | 779 | 731 | 1.04% | 22 | 36 | Township |
| Bainbridge | 11 | 724 | 682 | 0.98% | 1,805 | 0 | Town |
| Coatesville | 12 | 581 | 556 | 0.69% | 890 | 1 | Town |
| Fillmore | 13 | 561 | 534 | 0.9% | 288 | 2 | Town |
| Russellville | 14 | 320 | 301 | 0.95% | 1,592 | 0 | Town |
Bainbridge is the largest city in Putnam County, with a population of 17,561.
Russellville is the smallest city in Putnam County, with a population of 320.
There are 14 cities in Putnam County, Indiana.