37 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Shelbyville | 1 | 4,512 | 4,650 | -0.62% | 1,105 | 4 | City |
| Shelbyville | 2 | 4,358 | 4,483 | -0.52% | 128 | 34 | Township |
| Lakewood | 3 | 4,291 | 4,270 | 0.09% | 935 | 5 | Village |
| Rose | 4 | 1,871 | 1,912 | -0.27% | 53 | 35 | Township |
| Windsor | 5 | 1,336 | 1,378 | -0.45% | 47 | 29 | Township |
| Prairie | 6 | 1,198 | 1,207 | -0.17% | 22 | 54 | Township |
| Windsor | 7 | 1,029 | 1,069 | -0.77% | 1,633 | 1 | City |
| Tower Hill | 8 | 952 | 966 | -0.1% | 27 | 35 | Township |
| Dry Point | 9 | 938 | 956 | -0.11% | 39 | 24 | Township |
| Okaw | 10 | 877 | 890 | 0.11% | 28 | 31 | Township |
| Richland | 11 | 786 | 809 | -0.38% | 22 | 36 | Township |
| Oconee | 12 | 773 | 784 | 0.13% | 14 | 55 | Township |
| Stewardson | 13 | 717 | 719 | -0.14% | 1,170 | 1 | Village |
| Sigel | 14 | 710 | 721 | 0% | 30 | 24 | Township |
| Windsor | 15 | 647 | 669 | -0.77% | 1,477 | 0 | Village |
| Findlay | 16 | 644 | 666 | -0.77% | 697 | 1 | Village |
| Big Spring | 17 | 607 | 614 | 0.17% | 21 | 29 | Township |
| Herrick | 18 | 538 | 543 | 0.19% | 31 | 17 | Township |
| Strasburg | 19 | 513 | 533 | -0.77% | 948 | 1 | Village |
| Cowden | 20 | 495 | 514 | -0.8% | 1,231 | 0 | Village |
| Tower Hill | 21 | 471 | 481 | -0.42% | 469 | 1 | Village |
| Todds Point | 22 | 455 | 466 | -0.22% | 24 | 19 | Township |
| Flat Branch | 23 | 414 | 419 | 0.24% | 12 | 34 | Township |
| Ash Grove | 24 | 409 | 413 | 0% | 10 | 42 | Township |
| Ridge | 25 | 404 | 412 | -0.49% | 11 | 35 | Township |
| Holland | 26 | 386 | 392 | -0.26% | 14 | 27 | Township |
| Lakewood | 27 | 385 | 391 | -0.26% | 13 | 30 | Township |
| Herrick | 28 | 357 | 362 | -0.28% | 975 | 0 | Village |
| Clarksburg | 29 | 357 | 361 | -0.28% | 13 | 27 | Township |
| Cold Spring | 30 | 317 | 322 | 0% | 9 | 35 | Township |
| Sigel | 31 | 315 | 323 | -0.63% | 1,121 | 0 | Town |
| Rural | 32 | 308 | 312 | -0.65% | 9 | 35 | Township |
| Pickaway | 33 | 149 | 152 | -0.67% | 5 | 30 | Township |
| Oconee | 34 | 135 | 139 | -0.74% | 379 | 0 | Village |
| Penn | 35 | 82 | 86 | -1.2% | 3 | 24 | Township |
| Lakewood | 36 | 24 | 32 | 9.09% | 60 | 0 | CDP |
| Westervelt | 37 | 3 | 33 | -72.73% | 35 | 0 | CDP |
Shelbyville is the largest city in Shelby County, with a population of 4,512.
Westervelt is the smallest city in Shelby County, with a population of 3.
There are 37 cities in Shelby County, Illinois.