5 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Cairo | 1 | 1,426 | 1,716 | -3.26% | 204 | 7 | City |
| Tamms | 2 | 350 | 419 | -3.05% | 150 | 2 | Village |
| East Cape Girardeau | 3 | 236 | 286 | -3.28% | 120 | 2 | Village |
| McClure | 4 | 210 | 252 | -3.23% | 137 | 2 | Village |
| Thebes | 5 | 170 | 205 | -3.41% | 97 | 2 | Village |
Cairo is the largest city in Alexander County, with a population of 1,426.
Thebes is the smallest city in Alexander County, with a population of 170.
There are 5 cities in Alexander County, Illinois.