| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Ashland | 1 | 20,886 | 21,592 | -0.52% | 1,946 | 11 | City |
| Catlettsburg | 2 | 1,712 | 1,769 | -0.58% | 1,283 | 1 | City |
| Bellefonte | 3 | 873 | 912 | -0.91% | 991 | 1 | City |
Ashland is the largest city in Boyd County, with a population of 20,886.
Bellefonte is the smallest city in Boyd County, with a population of 873.
There are 3 cities in Boyd County, Kentucky.