| General Information about Area Code 303 | |
|---|---|
| Country | United States |
| State / Province / Territory | Colorado |
| Major City | Denver |
| Time Zone | Mountain (UTC-07:00) |
| Prefix | Primary City | County | Phone Type |
|---|---|---|---|
| 303-417 | Denver | Denver | Landline |
| 303-763 | Denver | Denver | Landline |
| 303-803 | Denver | Denver | Landline |
| 303-297 | Denver | Denver | Landline |
| 303-814 | Denver | Denver | Landline |
| 303-478 | Denver | Denver | Wireless |
| 303-223 | Denver | Denver | Landline |
| 303-909 | Denver | Denver | Wireless |
| 303-906 | Denver | Denver | Wireless |
| 303-787 | Denver | Denver | Landline |
| 303-484 | Denver | Denver | Landline |
| 303-655 | Brighton | Adams | Landline |
| 303-717 | Fort Lupton | Weld | Wireless |
| 303-821 | Denver | Denver | Wireless |
| 303-323 | Denver | Denver | Landline |
| 303-827 | Longmont | Boulder | Landline |
| 303-702 | Longmont | Boulder | Landline |
| 303-381 | Denver | Denver | Landline |
| 303-359 | Denver | Denver | Wireless |
| 303-448 | Denver | Denver | Landline |