Area Codes > 605 > Central Office Codes
| Exchange | Rate Center | State | Operating Company |
|---|---|---|---|
| 605-988 | SIOUX FLS | SD | QWEST CORPORATION |
| 605-990 | MITCHELL | SD | SANCOM, INC. DBA MITCHELL TELECOM - SD |
| 605-993 | WASTA | SD | GOLDEN WEST TELEPHONE COOPERATIVE, INC. |
| 605-994 | HECLA | SD | JAMES VALLEY COOPERATIVE TELEPHONE COMPANY |
| 605-995 | MITCHELL | SD | QWEST CORPORATION |
| 605-996 | MITCHELL | SD | QWEST CORPORATION |
| 605-997 | FLANDREAU | SD | QWEST CORPORATION |
| 605-999 | MITCHELL | SD | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD |