| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Greencastle | 1 | 9,935 | 9,827 | 0.11% | 1,906 | 5 | City |
| Cloverdale | 2 | 2,203 | 2,053 | 1.33% | 632 | 3 | Town |
| Roachdale | 3 | 873 | 832 | 0.92% | 1,722 | 1 | Town |
| Bainbridge | 4 | 714 | 679 | 0.99% | 1,781 | 0 | Town |
| Coatesville | 5 | 576 | 556 | 0.52% | 882 | 1 | Town |
| Fillmore | 6 | 557 | 534 | 0.72% | 286 | 2 | Town |
| Russellville | 7 | 316 | 302 | 0.96% | 1,572 | 0 | Town |
Greencastle is the largest city in Putnam County, with a population of 9,935.
Russellville is the smallest city in Putnam County, with a population of 316.
There are 7 cities in Putnam County, Indiana.