39 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Peoria | 1 | 111,384 | 112,942 | -0.28% | 2,314 | 48 | City |
| Peoria City | 2 | 96,992 | 97,717 | 0.43% | 2,421 | 40 | Township |
| Limestone | 3 | 18,269 | 18,289 | 0.73% | 511 | 36 | Township |
| Medina | 4 | 14,027 | 14,037 | 0.6% | 523 | 27 | Township |
| Kickapoo | 5 | 8,243 | 8,256 | 0.56% | 256 | 32 | Township |
| Chillicothe | 6 | 8,208 | 8,241 | 0.56% | 455 | 18 | Township |
| Chillicothe | 7 | 6,037 | 6,111 | -0.25% | 1,145 | 5 | City |
| Richwoods | 8 | 5,824 | 5,896 | 0.34% | 1,954 | 3 | Township |
| Bartonville | 9 | 5,812 | 5,929 | -0.41% | 722 | 8 | Village |
| Peoria Heights | 10 | 5,779 | 5,894 | -0.4% | 2,318 | 2 | Village |
| Radnor | 11 | 5,221 | 5,241 | 0.56% | 142 | 37 | Township |
| West Peoria | 12 | 4,190 | 4,257 | -0.33% | 1,990 | 2 | City |
| Elmwood | 13 | 2,476 | 2,500 | 0.36% | 69 | 36 | Township |
| Timber | 14 | 2,267 | 2,273 | 0.71% | 63 | 36 | Township |
| Elmwood | 15 | 2,033 | 2,070 | -0.39% | 1,456 | 1 | City |
| Bellevue | 16 | 1,910 | 1,874 | 0.37% | 859 | 2 | Village |
| Hollis | 17 | 1,808 | 1,812 | 0.56% | 76 | 24 | Township |
| Jubilee | 18 | 1,762 | 1,762 | 0.69% | 49 | 36 | Township |
| Princeville | 19 | 1,718 | 1,723 | -0.06% | 1,014 | 2 | Village |
| Princeville | 20 | 1,632 | 1,631 | 0.55% | 45 | 36 | Township |
| Rome | 21 | 1,609 | 1,656 | -0.62% | 44 | 36 | Township |
| Dunlap | 22 | 1,592 | 1,612 | -0.25% | 572 | 3 | Village |
| Rome | 23 | 1,572 | 1,394 | -0.69% | 817 | 2 | CDP |
| Hallock | 24 | 1,569 | 1,573 | 0.58% | 43 | 36 | Township |
| Lake Camelot | 25 | 1,535 | 1,631 | -0.65% | 882 | 2 | CDP |
| Hanna City | 26 | 1,244 | 1,263 | -0.32% | 914 | 1 | Village |
| Rosefield | 27 | 1,218 | 1,221 | 0.58% | 33 | 36 | Township |
| Brimfield | 28 | 1,173 | 1,174 | 0.77% | 32 | 36 | Township |
| Akron | 29 | 1,001 | 1,001 | 0.4% | 28 | 36 | Township |
| Trivoli | 30 | 999 | 1,001 | 0.6% | 28 | 36 | Township |
| Glasford | 31 | 846 | 860 | -0.35% | 932 | 1 | Village |
| Brimfield | 32 | 768 | 777 | -0.26% | 834 | 1 | Village |
| Trivoli | 33 | 542 | 380 | 7.11% | 356 | 2 | CDP |
| Norwood | 34 | 432 | 437 | -0.23% | 1,407 | 0 | Village |
| Mossville | 35 | 275 | 263 | 7% | 220 | 1 | CDP |
| Kingston Mines | 36 | 266 | 271 | -0.37% | 184 | 1 | Village |
| Smithville | 37 | 266 | 171 | 7.26% | 210 | 1 | CDP |
| Mapleton | 38 | 252 | 257 | -0.4% | 285 | 1 | Village |
| West Peoria | 39 | 0 | 0 | 0.00 | 2 | Township |
Peoria is the largest city in Peoria County, with a population of 111,384.
West Peoria is the smallest city in Peoria County, with a population of 0.
There are 39 cities in Peoria County, Illinois.