| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Napa | 1 | 75,990 | 79,341 | -0.75% | 4,210 | 18 | City |
| American Canyon | 2 | 22,830 | 21,802 | 0.25% | 3,757 | 6 | City |
| St. Helena | 3 | 5,149 | 5,421 | -0.87% | 1,039 | 5 | City |
| Calistoga | 4 | 4,900 | 5,227 | -1.09% | 1,900 | 3 | City |
| Yountville | 5 | 3,161 | 3,423 | -1.16% | 2,121 | 1 | City |
Napa is the largest city in Napa County, with a population of 75,990.
Yountville is the smallest city in Napa County, with a population of 3,161.
There are 5 cities in Napa County, California.