Phone numbers in Spearfish, South Dakota
Spearfish has 20 phone prefixes in area code 605.
Biggest holders: Verizon Wireless, CenturyLink / Lumen, Midcontinent Communications. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 35%
- Local phone company 25%
- Internet / business phone carrier 15%
- Phone company 25%
Every prefix in Spearfish
Search the first six digits of a number in this list. If it's here, the number started in Spearfish with the carrier shown. If it isn't, check the South Dakota page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 605-269 | CenturyLink / Lumen | Local phone company | – |
| 605-340 | Onvoy | Internet / business phone carrier | 2001 |
| 605-443 | Midcontinent Communications | Phone company | – |
| 605-549 | Bandwidth | Internet / business phone carrier | 2010 |
| 605-559 | Midcontinent Communications | Phone company | 2006 |
| 605-566 | Onvoy | Internet / business phone carrier | – |
| 605-571 | Midcontinent Communications | Phone company | – |
| 605-578 | CenturyLink / Lumen | Local phone company | – |
| 605-580 | Verizon Wireless | Mobile carrier | – |
| 605-584 | CenturyLink / Lumen | Local phone company | – |
| 605-591 | Verizon Wireless | Mobile carrier | – |
| 605-631 | Verizon Wireless | Mobile carrier | – |
| 605-639 | Verizon Wireless | Mobile carrier | – |
| 605-641 | AT&T Mobility | Mobile carrier | – |
| 605-642 | CenturyLink / Lumen | Local phone company | – |
| 605-644 | CenturyLink / Lumen | Local phone company | – |
| 605-645 | Verizon Wireless | Mobile carrier | – |
| 605-717 | Bluepeak | Phone company | 2001 |
| 605-722 | Bluepeak | Phone company | – |
| 605-920 | Verizon Wireless | Mobile carrier | – |
Most prefixes are pooled: the 10,000 numbers in each are handed out in blocks of 1,000 to different carriers, and people can also take their numbers to another carrier. So the carrier shown is where the prefix started, not a guarantee about any one number. Source: NANPA central office code records, 2026-10-10.