| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Oquawka | 1 | 1,051 | 1,129 | -1.31% | 715 | 1 | Village |
| Stronghurst | 2 | 748 | 811 | -1.58% | 857 | 1 | Village |
| Lomax | 3 | 370 | 403 | -1.6% | 311 | 1 | Village |
| Biggsville | 4 | 278 | 302 | -1.42% | 825 | 0 | Village |
| Gladstone | 5 | 215 | 232 | -1.38% | 597 | 0 | Village |
| Media | 6 | 108 | 119 | -1.82% | 64 | 2 | Village |
| Raritan | 7 | 96 | 104 | -2.04% | 1,011 | 0 | Village |
| Gulfport | 8 | 38 | 41 | -2.56% | 27 | 1 | Village |
Oquawka is the largest city in Henderson County, with a population of 1,051.
Gulfport is the smallest city in Henderson County, with a population of 38.
There are 8 cities in Henderson County, Illinois.