| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Indian Trail | 1 | 45,201 | 40,370 | 2.03% | 1,983 | 23 | Town |
| Monroe | 2 | 44,007 | 34,699 | 3.2% | 1,337 | 33 | City |
| Waxhaw | 3 | 23,746 | 20,781 | 2.62% | 1,837 | 13 | Town |
| Stallings | 4 | 18,117 | 16,192 | 2.01% | 2,162 | 8 | Town |
| Wesley Chapel | 5 | 9,759 | 8,719 | 2.02% | 1,004 | 10 | Village |
| Unionville | 6 | 7,471 | 6,667 | 2.03% | 255 | 29 | Town |
| Marvin | 7 | 7,182 | 6,417 | 2.02% | 1,198 | 6 | Village |
| Wingate | 8 | 4,702 | 4,310 | 1.6% | 1,793 | 3 | Town |
| Lake Park | 9 | 3,680 | 3,301 | 1.97% | 5,007 | 1 | Village |
| Mineral Springs | 10 | 3,585 | 3,201 | 2.02% | 424 | 8 | Town |
| Marshville | 11 | 2,784 | 2,540 | 1.64% | 1,312 | 2 | Town |
| Hemby Bridge | 12 | 1,798 | 1,616 | 1.93% | 785 | 2 | Town |
Indian Trail is the largest city in Union County, with a population of 45,201.
Hemby Bridge is the smallest city in Union County, with a population of 1,798.
There are 12 cities in Union County, North Carolina.