43 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Avon | 1 | 64,221 | 63,599 | 0.48% | 2,862 | 22 | Township |
| Cuba | 2 | 17,510 | 17,249 | 0.49% | 767 | 23 | Township |
| Canton | 3 | 13,634 | 14,245 | -0.53% | 392 | 35 | Township |
| Canton | 4 | 12,673 | 13,341 | -0.87% | 1,510 | 8 | City |
| Farmington | 5 | 3,063 | 3,203 | -0.49% | 86 | 36 | Township |
| Lewistown | 6 | 2,541 | 2,664 | -0.55% | 72 | 35 | Township |
| Farmington | 7 | 2,250 | 2,385 | -0.97% | 1,495 | 2 | City |
| Lewistown | 8 | 1,919 | 2,042 | -1.03% | 960 | 2 | City |
| Putman | 9 | 1,891 | 1,973 | -0.53% | 56 | 34 | Township |
| Buckheart | 10 | 1,263 | 1,316 | -0.47% | 36 | 35 | Township |
| Astoria | 11 | 1,177 | 1,238 | -0.68% | 33 | 36 | Township |
| Cuba | 12 | 1,114 | 1,182 | -0.98% | 2,052 | 1 | City |
| Astoria | 13 | 868 | 925 | -1.03% | 1,481 | 1 | Town |
| Vermont | 14 | 801 | 826 | -0.37% | 22 | 37 | Township |
| Pleasant | 15 | 691 | 720 | -0.43% | 19 | 37 | Township |
| Avon | 16 | 657 | 698 | -1.05% | 1,480 | 0 | Village |
| Fairview | 17 | 600 | 630 | -0.83% | 17 | 36 | Township |
| Vermont | 18 | 553 | 571 | -0.54% | 440 | 1 | Village |
| Liverpool | 19 | 544 | 563 | -0.55% | 14 | 40 | Township |
| Cass | 20 | 538 | 550 | 0% | 14 | 39 | Township |
| Young Hickory | 21 | 530 | 542 | 0% | 22 | 24 | Township |
| St. David | 22 | 494 | 526 | -1% | 1,529 | 0 | Village |
| Joshua | 23 | 423 | 431 | 0% | 12 | 35 | Township |
| Ipava | 24 | 418 | 442 | -0.95% | 1,560 | 0 | Village |
| Fairview | 25 | 402 | 426 | -0.99% | 95 | 4 | Village |
| Farmers | 26 | 349 | 363 | -0.29% | 10 | 36 | Township |
| London Mills | 27 | 338 | 350 | -0.59% | 494 | 1 | Village |
| Table Grove | 28 | 325 | 349 | -1.22% | 1,152 | 0 | Village |
| Banner | 29 | 316 | 317 | 0.32% | 11 | 28 | Township |
| Harris | 30 | 309 | 316 | 0% | 9 | 34 | Township |
| Dunfermline | 31 | 247 | 261 | -0.8% | 1,680 | 0 | Village |
| Bernadotte | 32 | 242 | 253 | -0.82% | 6 | 38 | Township |
| Smithfield | 33 | 182 | 188 | -0.55% | 391 | 0 | Village |
| Isabel | 34 | 168 | 174 | -0.59% | 6 | 29 | Township |
| Bryant | 35 | 163 | 166 | 0% | 657 | 0 | Village |
| Norris | 36 | 163 | 174 | -1.21% | 576 | 0 | Village |
| Waterford | 37 | 158 | 163 | -0.63% | 8 | 21 | Township |
| Banner | 38 | 157 | 160 | 0% | 122 | 1 | Village |
| Ellisville | 39 | 150 | 153 | 0% | 11 | 14 | Township |
| Marietta | 40 | 99 | 102 | 0% | 363 | 0 | Village |
| Liverpool | 41 | 89 | 94 | -1.11% | 1,060 | 0 | Village |
| Ellisville | 42 | 83 | 88 | -1.19% | 306 | 0 | Village |
| Kerton | 43 | 81 | 83 | 0% | 3 | 24 | Township |
Avon is the largest city in Fulton County, with a population of 64,221.
Kerton is the smallest city in Fulton County, with a population of 81.
There are 43 cities in Fulton County, Illinois.