37 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hillsboro township | 1 | 6,757 | 6,943 | -0.63% | 187 | 36.12 | Township |
| Litchfield | 2 | 6,516 | 6,761 | -0.75% | 727 | 8.96 | City |
| Hillsboro | 3 | 5,715 | 5,860 | -0.5% | 662 | 8.63 | City |
| North Litchfield township | 4 | 4,749 | 4,942 | -0.92% | 131 | 36.16 | Township |
| South Litchfield township | 5 | 3,154 | 3,282 | -0.94% | 85 | 37.15 | Township |
| Nokomis township | 6 | 2,660 | 2,777 | -1.04% | 73 | 36.40 | Township |
| Nokomis | 7 | 2,059 | 2,138 | -0.77% | 1,630 | 1.26 | City |
| East Fork township | 8 | 1,968 | 2,045 | -0.91% | 34 | 58.01 | Township |
| Raymond township | 9 | 1,088 | 1,130 | -0.91% | 30 | 36.06 | Township |
| Witt township | 10 | 981 | 1,024 | -1.01% | 27 | 36.76 | Township |
| Raymond | 11 | 907 | 942 | -0.77% | 722 | 1.26 | Village |
| Bois D'Arc township | 12 | 892 | 928 | -0.89% | 16 | 54.55 | Township |
| Butler township | 13 | 842 | 880 | -0.59% | 12 | 71.89 | Township |
| Irving township | 14 | 840 | 879 | -1.18% | 24 | 34.35 | Township |
| Witt | 15 | 752 | 782 | -0.79% | 607 | 1.24 | City |
| Taylor Springs | 16 | 722 | 736 | -0.41% | 684 | 1.05 | Village |
| Butler Grove township | 17 | 708 | 733 | -0.84% | 20 | 35.72 | Township |
| Farmersville | 18 | 659 | 684 | -0.75% | 932 | 0.71 | Village |
| Coffeen | 19 | 622 | 642 | -0.64% | 535 | 1.16 | City |
| Grisham township | 20 | 598 | 621 | -0.99% | 25 | 24.36 | Township |
| Schram City | 21 | 543 | 563 | -0.73% | 959 | 0.57 | Village |
| Audubon township | 22 | 489 | 509 | -1.01% | 9 | 53.97 | Township |
| Zanesville township | 23 | 403 | 423 | -1.23% | 11 | 36.63 | Township |
| Pitman township | 24 | 392 | 401 | -0.51% | 11 | 36.45 | Township |
| Irving | 25 | 359 | 373 | -0.83% | 400 | 0.90 | Village |
| Raymond township | 26 | 332 | 353 | -1.48% | 9 | 36.25 | Township |
| Panama | 27 | 323 | 332 | -0.62% | 885 | 0.36 | Village |
| Walshville township | 28 | 310 | 320 | -0.64% | 8 | 36.75 | Township |
| Fillmore | 29 | 295 | 302 | -0.34% | 444 | 0.66 | Village |
| Rountree township | 30 | 219 | 228 | -0.9% | 6 | 35.81 | Township |
| Harvel township | 31 | 183 | 192 | -1.08% | 10 | 18.02 | Township |
| Waggoner | 32 | 178 | 180 | 0% | 730 | 0.24 | Village |
| Harvel | 33 | 167 | 174 | -0.6% | 232 | 0.72 | Village |
| Butler | 34 | 163 | 165 | 0% | 273 | 0.60 | Village |
| Donnellson | 35 | 147 | 152 | -0.68% | 396 | 0.37 | Village |
| Ohlman | 36 | 106 | 111 | -0.93% | 330 | 0.32 | Village |
| Walshville | 37 | 60 | 62 | 0% | 236 | 0.25 | Village |
Hillsboro township is the largest city in Montgomery County, with a population of 6,757.
Walshville is the smallest city in Montgomery County.
There are 37 cities in Montgomery County, Illinois.