| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Lake Butler | 1 | 1,923 | 1,924 | 0.1% | 816 | 2 | City |
| Worthington Springs | 2 | 381 | 377 | 0.26% | 397 | 1 | Town |
| Raiford | 3 | 227 | 221 | 0.44% | 417 | 1 | Town |
Lake Butler is the largest city in Union County, with a population of 1,923.
Raiford is the smallest city in Union County, with a population of 227.
There are 3 cities in Union County, Florida.