Founded on 1861-11-01, Jefferson County is one of 64 counties in the state of Colorado. Historically, Jefferson County was formed from Created as one of the 17 original counties of the Territory of Colorado. The city of Golden is the county seat. With FIPS code of 59, Jefferson County has a population of 579,581 and area of 772.85 square miles (2,002 km2).
List of all cities in Jefferson County, CO alphabetically
| City/Town | Postal Code | Area Code |
| Arvada, CO | 80001 | 303/720 |
| 80002 | 303/720 | |
| 80003 | 303/720 | |
| 80004 | 303/720 | |
| 80005 | 303/720 | |
| 80006 | 303/720 | |
| 80007 | 303/720 | |
| 80021 | 303/720 | |
| 80403 | 303/720 | |
| Aspen Park, CO | 80433 | 303/720 |
| Blackhawk, CO | 80403 | 303/720 |
| Bow Mar, CO | 80123 | 303/720 |
| Broomfield, CO | 80021 | 303/720 |
| Buffalo Creek, CO | 80425 | 303/720 |
| Centennial, CO | 80123 | 303/720 |
| Columbine Valley, CO | 80123 | 303/720 |
| Conifer, CO | 80433 | 303/720 |
| Denver, CO | 80002 | 303/720 |
| 80033 | 303/720 | |
| 80123 | 303/720 | |
| 80127 | 303/720 | |
| 80214 | 303/720 | |
| 80215 | 303/720 | |
| 80225 | 303/720 | |
| 80226 | 303/720 | |
| 80227 | 303/720 | |
| 80228 | 303/720 | |
| 80232 | 303/720 | |
| 80235 | 303/720 | |
| Denver Federal Center, CO | 80225 | 303/720 |
| Edgewater, CO | 80214 | 303/720 |
| Evergreen, CO | 80401 | 303/720 |
| 80437 | 303/720 | |
| 80439 | 303/720 | |
| Foxton, CO | 80433 | 303/720 |
| Golden, CO | 80401 | 303/720 |
| 80402 | 303/720 | |
| 80403 | 303/720 | |
| 80419 | 303/720 | |
| 80439 | 303/720 | |
| Grants Ranch, CO | 80123 | 303/720 |
| Idledale, CO | 80453 | 303/720 |
| Indian Hills, CO | 80454 | 303/720 |
| Jefferson County, CO | 80419 | 303/720 |
| Kittredge, CO | 80457 | 303/720 |
| Lakewood, CO | 80123 | 303/720 |
| 80214 | 303/720 | |
| 80215 | 303/720 | |
| 80225 | 303/720 | |
| 80226 | 303/720 | |
| 80227 | 303/720 | |
| 80228 | 303/720 | |
| 80232 | 303/720 | |
| 80235 | 303/720 | |
| 80401 | 303/720 | |
| Littleton, CO | 80123 | 303/720 |
| 80127 | 303/720 | |
| 80128 | 303/720 | |
| 80162 | 303/720 | |
| Morrison, CO | 80465 | 303/720 |
| Pine, CO | 80470 | 303/720 |
| Rollinsville, CO | 80403 | 303/720 |
| Westminster, CO | 80003 | 303/720 |
| 80005 | 303/720 | |
| 80021 | 303/720 | |
| Wheat Ridge, CO | 80002 | 303/720 |
| 80033 | 303/720 | |
| 80034 | 303/720 | |
| 80214 | 303/720 | |
| 80215 | 303/720 |
Map of Cities in Jefferson County, CO
