Costilla County, Colorado Cities (2025)

3 cities

City
Rank
2025 Pop.
2020 Pop.
Change
Density
Area (mi²)
Type
San Luis16356021.11%1,1200.57 Town
Fort Garland26196071.98%1,6460.38 CDP
Blanca33443231.18%1881.83 Town

Costilla County Cities Summary

Largest City

San Luis is the largest city in Costilla County, with a population of 635.

Smallest City

Blanca is the smallest city in Costilla County.

10 Largest Cities

There are 3 cities in Costilla County, Colorado.

Location of Costilla County