Costilla County, Colorado
Costilla County, Colorado, has 3,679 residents (July 2025 estimate). Its county seat is San Luis. It uses Mountain Time and covers 1,228 sq mi (3,179 km²) of land.
- Resident population, July 2025
- 3,679
- Land area
- 1,228 sq mi (3,179 km²)
- County seat or government
- San Luis
- Time zone
- Mountain TimeUTC-07:00 in January; UTC-06:00 in July
- Median household income
- $36,861 ± $6,112
- Median home value
- $184,700 ± $34,905
- Median rent, with utilities
- $927 ± $134
- Homes lived in by their owners
- 79% ± 4.0 points
- County type
- County
- Metro or micro area
- Alamosa, CO micro areaOutlying county
- Water area
- 3.41 sq mi (8.83 km²)
- State
- Colorado
- County code (FIPS)
- 08023
- Coordinates (central point)
- 37.277547, -105.428940
These coordinates mark a central point for the area, not a street address. Income, home value, rent and homes lived in by their owners: U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, ± margin at 90% confidence; checked on October 13, 2026.
Time zones in Costilla County
| Time zone | Local time and UTC offset | Next clock change |
|---|---|---|
| Mountain TimeAmerica/Denver | UTC-07:00 in January; UTC-06:00 in July. Enable JavaScript for the live clock. | Enable JavaScript for upcoming changes. |
Near a time-zone line, check where you are with the time-zone finder. Your phone’s setting can differ.
ZIP Code areas, largest first
- 811511,716 people
- 810551,559 people
- 811521,244 people
- 811331,085 people
- 81123606 people
- 81126506 people
- 8113817 people
7 ZIP Code areas overlap Costilla County. People counts are 2020–2024 estimates for each whole ZIP area. Mailing ZIPs can differ; check an address with USPS ZIP Code Lookup.
Official county information
Costilla County government website ↗ is the next stop for county offices, tax, voting, jury and records information. A geographic lookup cannot determine eligibility, tax liability or a court obligation.
School districts in Costilla County, largest first
- Centennial School District R-11,916 people
- Sierra Grande School District R-301,691 people
Districts with land in the county; a district can cross county lines. People counts are American Community Survey 2020–2024 5-year estimates. A district boundary doesn’t decide which school a student attends.
Cities, towns and communities, largest first
These areas overlap the mapped boundary; an overlap does not mean that every address belongs to both.
- San Luis, Colorado (town)560 people
- Fort Garland, Colorado (CDP)446 people
- Blanca, Colorado (town)230 people
- San Acacio, Colorado (CDP)61 people
Bordering areas, nearest first
Distances are straight lines between map points.
- Alamosa County, Colorado28 mi northwest
- Huerfano County, Colorado38 mi northeast
- Conejos County, Colorado41 mi west
- Taos County, New Mexico50 mi south
- Colfax County, New Mexico63 mi southeast
- Las Animas County, Colorado76 mi east
Before using this answer on a form
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