10 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Granville | 1 | 2,785 | 2,773 | 0.58% | 62 | 45 | Township |
| Granville | 2 | 1,318 | 1,357 | -0.45% | 1,008 | 1 | Village |
| Hennepin | 3 | 1,259 | 1,236 | 0.8% | 30 | 41 | Township |
| Magnolia | 4 | 1,034 | 1,010 | 1.08% | 24 | 42 | Township |
| Hennepin | 5 | 741 | 759 | -0.4% | 140 | 5 | Village |
| Senachwine | 6 | 645 | 612 | 1.26% | 20 | 32 | Township |
| Mark | 7 | 502 | 516 | -0.4% | 471 | 1 | Village |
| McNabb | 8 | 271 | 279 | -0.37% | 1,531 | 0 | Village |
| Magnolia | 9 | 252 | 258 | -0.4% | 805 | 0 | Village |
| Standard | 10 | 219 | 227 | -0.45% | 308 | 1 | Village |
Granville is the largest city in Putnam County, with a population of 2,785.
Standard is the smallest city in Putnam County, with a population of 219.
There are 10 cities in Putnam County, Illinois.