30 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Decatur | 1 | 67,655 | 70,978 | -0.81% | 1,532 | 44 | City |
| Decatur | 2 | 45,897 | 47,517 | -0.11% | 1,579 | 29 | Township |
| Hickory Point | 3 | 17,722 | 18,195 | 0.03% | 498 | 36 | Township |
| Long Creek | 4 | 10,263 | 10,559 | 0.04% | 269 | 38 | Township |
| Mount Zion | 5 | 7,064 | 7,190 | 0.16% | 106 | 67 | Township |
| Mount Zion | 6 | 5,838 | 6,015 | -0.49% | 1,368 | 4 | Village |
| Whitmore | 7 | 4,192 | 4,305 | 0.05% | 117 | 36 | Township |
| South Wheatland | 8 | 3,922 | 4,025 | 0.1% | 141 | 28 | Township |
| Forsyth | 9 | 3,618 | 3,732 | -0.52% | 1,169 | 3 | Village |
| Maroa | 10 | 1,809 | 1,853 | 0.17% | 43 | 42 | Township |
| Harristown | 11 | 1,711 | 1,758 | 0.12% | 61 | 28 | Township |
| Maroa | 12 | 1,511 | 1,576 | -0.72% | 857 | 2 | City |
| South Macon | 13 | 1,423 | 1,461 | 0.21% | 42 | 34 | Township |
| Pleasant View | 14 | 1,366 | 1,417 | -0.15% | 45 | 31 | Township |
| Friends Creek | 15 | 1,328 | 1,371 | 0% | 27 | 49 | Township |
| Illini | 16 | 1,300 | 1,335 | -0.08% | 35 | 37 | Township |
| Harristown | 17 | 1,249 | 1,312 | -0.79% | 695 | 2 | Village |
| Long Creek | 18 | 1,217 | 1,261 | -0.57% | 431 | 3 | Village |
| Macon | 19 | 1,115 | 1,169 | -0.8% | 880 | 1 | City |
| Warrensburg | 20 | 1,073 | 1,112 | -0.56% | 1,474 | 1 | Village |
| Blue Mound | 21 | 1,070 | 1,130 | -0.93% | 1,829 | 1 | Village |
| Oakley | 22 | 958 | 981 | 0.21% | 33 | 29 | Township |
| Argenta | 23 | 864 | 911 | -0.92% | 1,323 | 1 | Village |
| Oreana | 24 | 843 | 888 | -0.82% | 1,801 | 0 | Village |
| Blue Mound | 25 | 795 | 812 | 0.13% | 24 | 33 | Township |
| Niantic | 26 | 727 | 752 | 0% | 25 | 29 | Township |
| Niantic | 27 | 577 | 609 | -0.86% | 555 | 1 | Village |
| Blue Mound | 28 | 388 | 388 | 0.26% | 10 | 38 | Township |
| Austin | 29 | 226 | 233 | 0% | 6 | 37 | Township |
| Macon | 30 | 198 | 205 | -0.5% | 5 | 37 | Township |
Decatur is the largest city in Macon County, with a population of 67,655.
Macon is the smallest city in Macon County, with a population of 198.
There are 30 cities in Macon County, Illinois.