10 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Granville township | 1 | 2,718 | 2,771 | -0.04% | 61 | 44.64 | Township |
| Granville | 2 | 1,293 | 1,357 | -1% | 989 | 1.31 | Village |
| Hennepin township | 3 | 1,231 | 1,236 | 0.33% | 30 | 41.39 | Township |
| Magnolia township | 4 | 1,003 | 1,011 | 0.1% | 24 | 42.24 | Township |
| Hennepin | 5 | 729 | 759 | -0.82% | 137 | 5.31 | Village |
| Senachwine township | 6 | 625 | 612 | 0.64% | 20 | 31.83 | Township |
| Mark | 7 | 496 | 516 | -0.8% | 466 | 1.06 | Village |
| McNabb | 8 | 265 | 279 | -1.12% | 1,497 | 0.18 | Village |
| Magnolia | 9 | 243 | 253 | -0.82% | 776 | 0.31 | Village |
| Standard | 10 | 212 | 226 | -1.4% | 298 | 0.71 | Village |
Granville township is the largest city in Putnam County, with a population of 2,718.
Standard is the smallest city in Putnam County.
There are 10 cities in Putnam County, Illinois.