| District of Colorado area codes: 720 | |
|---|---|
| Country | United States |
| State/Province | Colorado |
| Major City | Denver |
| Time Zone | Mountain |
| Prefix | County | Primary City | Company |
|---|---|---|---|
| 720-241 | Jefferson | Denver, CO | Xo Colorado |
| 720-242 | Jefferson | Denver, CO | Qwest Corporation |
| 720-243 | Jefferson | Denver, CO | Leap Wireless Intl DBA Cricket Comm |
| 720-244 | Jefferson | Denver, CO | New Cingular Wireless PCS |
| 720-245 | Denver | Denver, CO | Eschelon Telecom Of Colorado |
| 720-246 | Arapahoe | Englewood, CO | Xo Colorado |
| 720-247 | Adams | Brighton, CO | Xo Colorado |
| 720-248 | Denver | Denver, CO | Cbeyond Communications |
| 720-249 | Jefferson | Denver, CO | Xo Colorado |
| 720-250 | Jefferson | Denver, CO | Xo Colorado |
| 720-251 | Arapahoe | Aurora, CO | Level 3 Communications |
| 720-252 | Denver | Denver, CO | Sprint Spectrum L.p. |
| 720-253 | Denver | Denver, CO | Sprint Spectrum L.p. |
| 720-254 | Denver | Denver, CO | Sprint Spectrum L.p. |
| 720-255 | Denver | Denver, CO | Sprint Spectrum L.p. |
| 720-256 | Denver | Denver, CO | Sprint Spectrum L.p. |
| 720-257 | Jefferson | Denver, CO | Xo Colorado |
| 720-258 | Denver | Denver, CO | Teleport Communications America |
| 720-259 | Jefferson | Denver, CO | Level 3 Communications |
| 720-260 | Jefferson | Denver, CO | Sprint Spectrum L.p. |
There are 519 prefixes, In the code area, the major cities are Arvada, CO;Aurora, CO;Boulder, CO;Brighton, CO;Bro. The major city is Denver.