- Adams
- Alamosa
- Arapahoe
- Archuleta
- Baca
- Bent
- Boulder
- Chaffee
- Cheyenne
- Clear Creek
- Conejos
- Costilla
- Crowley
- Custer
- Delta
- Denver
- Dolores
- Douglas
- Eagle
- El Paso
- Elbert
- Fremont
- Garfield
- Gilpin
- Grand
- Gunnison
- Hinsdale
- Huerfano
- Jackson
- Jefferson
- Kiowa
- Kit Carson
- La Plata
- Lake
- Larimer
- Las Animas
- Lincoln
- Logan
- Mesa
- Mineral
- Moffat
- Montezuma
- Montrose
- Morgan
- Otero
- Ouray
- Park
- Phillips
- Pitkin
- Prowers
- Pueblo
- Rio Blanco
- Rio Grande
- Routt
- Saguache
- San Juan
- San Miguel
- Sedgwick
- Summit
- Teller
- Washington
- Weld
- Yuma
Counties by State
All the counties in Colorado (CO)
Click on one of the county names below, or use the search box to find the zip code information you need.
US Zip Code Information: