5 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Fairfax | 1 | 26,880 | 24,179 | 2.05% | 4,307 | 6 | City |
| Herndon | 2 | 25,328 | 24,588 | 0.59% | 5,909 | 4 | Town |
| Vienna | 3 | 16,590 | 16,448 | 0.17% | 3,768 | 4 | Town |
| Falls Church | 4 | 15,123 | 14,677 | 0.59% | 7,391 | 2 | City |
| Clifton | 5 | 242 | 242 | 0% | 988 | 0 | Town |
Fairfax is the largest city in Fairfax County, with a population of 26,880.
Clifton is the smallest city in Fairfax County, with a population of 242.
There are 5 cities in Fairfax County, Virginia.