5 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Morganfield | 1 | 3,069 | 3,253 | -1.19% | 1,091 | 2.81 | City |
| Breckinridge Center | 2 | 1,693 | 1,961 | -1.46% | 645 | 2.62 | CDP |
| Sturgis | 3 | 1,632 | 1,737 | -1.27% | 1,042 | 1.57 | City |
| Uniontown | 4 | 883 | 927 | -1.01% | 1,039 | 0.85 | City |
| Waverly | 5 | 298 | 313 | -1% | 1,116 | 0.27 | City |
Morganfield is the largest city in Union County, with a population of 3,069.
Waverly is the smallest city in Union County.
There are 5 cities in Union County, Kentucky.