| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Canton | 1 | 13,256 | 13,357 | -0.31% | 1,580 | 8 | City |
| Farmington | 2 | 2,275 | 2,393 | -1% | 1,512 | 2 | City |
| Lewistown | 3 | 1,942 | 2,043 | -1.02% | 971 | 2 | City |
| Cuba | 4 | 1,119 | 1,178 | -1.06% | 2,061 | 1 | City |
| Astoria | 5 | 873 | 919 | -1.02% | 1,490 | 1 | Town |
| Avon | 6 | 665 | 701 | -1.04% | 1,498 | 0 | Village |
| Vermont | 7 | 553 | 571 | -0.72% | 440 | 1 | Village |
| St. David | 8 | 499 | 527 | -1.19% | 1,545 | 0 | Village |
| Ipava | 9 | 413 | 437 | -1.2% | 1,541 | 0 | Village |
| Fairview | 10 | 406 | 424 | -0.98% | 96 | 4 | Village |
| London Mills | 11 | 340 | 350 | -0.58% | 497 | 1 | Village |
| Table Grove | 12 | 325 | 344 | -1.22% | 1,152 | 0 | Village |
| Dunfermline | 13 | 249 | 261 | -1.19% | 1,694 | 0 | Village |
| Smithfield | 14 | 180 | 185 | -0.55% | 387 | 0 | Village |
| Bryant | 15 | 167 | 170 | -0.6% | 673 | 0 | Village |
| Norris | 16 | 167 | 173 | -0.6% | 590 | 0 | Village |
| Banner | 17 | 165 | 170 | -0.6% | 128 | 1 | Village |
| Marietta | 18 | 96 | 99 | -1.03% | 352 | 0 | Village |
| Liverpool | 19 | 88 | 93 | -1.12% | 1,048 | 0 | Village |
| Ellisville | 20 | 84 | 88 | -1.18% | 310 | 0 | Village |
Canton is the largest city in Fulton County, with a population of 13,256.
Ellisville is the smallest city in Fulton County, with a population of 84.
There are 20 cities in Fulton County, Illinois.