NumberingData
Verified Nov 1, 2026 · Source: NANPA CO Code Assignment Records

SPEARFISH prefixes in area code 605

NANPA records 20 assigned NXX blocks to rate center SPEARFISH in area code 605, 2.7% of the 745 blocks assigned in the code. A rate center is the billing geography a block is allocated to – NANPA truncates the name to ten characters, so read it as a NANPA label rather than a town. 7 holders hold those blocks, the largest being CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD (6), QWEST CORPORATION (5), MIDCONTINENT COMMUNICATIONS. - SD (3). The earliest assignment on record here is 2001-02-07 and the most recent 2010-02-12. 13 of them are in thousands-block pooling, so those prefixes are shared between carriers in 1,000-number lots.

20 assigned blocks – 2.7% of 605
7 holders of record
13 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
605-269 Lumen QWEST CORPORATION – yes yes
605-340 Onvoy ONVOY, LLC - SD 2001-02-07 yes yes
605-443 MIDCONTINENT COMMUNICATIONS. - SD – yes yes
605-549 Bandwidth BANDWIDTH.COM CLEC, LLC - SD 2010-02-12 yes yes
605-559 MIDCONTINENT COMMUNICATIONS. - SD 2006-10-06 no yes
605-566 Onvoy ONVOY, LLC - SD – yes yes
605-571 MIDCONTINENT COMMUNICATIONS. - SD – yes yes
605-578 Lumen QWEST CORPORATION – yes yes
605-580 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD – yes yes
605-584 Lumen QWEST CORPORATION – no yes
605-591 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD – yes yes
605-631 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD – yes yes
605-639 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD – yes yes
605-641 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – no yes
605-642 Lumen QWEST CORPORATION – no yes
605-644 Lumen QWEST CORPORATION – yes yes
605-645 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD – no yes
605-717 CLARITY TELECOM, LLC DBA BLUEPEAK 2001-07-06 no yes
605-722 CLARITY TELECOM, LLC DBA BLUEPEAK – no yes
605-920 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD – yes yes

The holder is who received the block from the numbering administrator. It is not necessarily the carrier serving a given number: numbers move with their owners, and a pooled block is shared.

Who holds the blocks

HolderBrandBlocksShare here
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD Verizon 6 30%
QWEST CORPORATION Lumen 5 25%
MIDCONTINENT COMMUNICATIONS. - SD – 3 15%
ONVOY, LLC - SD Onvoy 2 10%
CLARITY TELECOM, LLC DBA BLUEPEAK – 2 10%
BANDWIDTH.COM CLEC, LLC - SD Bandwidth 1 5%
NEW CINGULAR WIRELESS PCS, LLC - IL AT&T 1 5%

Frequently asked

Which prefixes belong to SPEARFISH in area code 605?

20 blocks: 269, 340, 443, 549, 559, 566, 571, 578, 580, 584, 591, 631 and 8 more, all listed in the table above.

Which carriers have numbers in SPEARFISH?

CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD (6 blocks), QWEST CORPORATION (5 blocks), MIDCONTINENT COMMUNICATIONS. - SD (3 blocks), ONVOY, LLC - SD (2 blocks), CLARITY TELECOM, LLC DBA BLUEPEAK (2 blocks), BANDWIDTH.COM CLEC, LLC - SD (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is SPEARFISH a city?

It is a rate center – the unit NANPA allocates number blocks to. Its name is abbreviated to ten characters and is not necessarily a settlement: we print it as recorded rather than guess at the full name.

Other rate centers in 605

All 745 prefixes in 605