| Area Code | 605 |
| State | South Dakota |
| Current Time in Area Code 605 | 605> CDT |
| Timezone | Central Daylight Time |
| Regional Market Area | Minot-Bismark-Dickinson Area Rapid City Area Sioux City Area Sioux Falls Area |
| Metro Area(s) | Aberdeen, SD Brookings, SD Huron, SD Mitchell, SD Pierre, SD Rapid City, SD Sioux Falls, SD Spearfish, SD Vermillion, SD Watertown, SD Yankton, SD |
| Population (2020) | 886667 |
| Adjacent Area Codes | 218,307,308,320,402,406,507,531,701,712 |
| Rapid City |
| Sioux Falls |