NumberResearch Membership · Data 09/20/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/20/2026

Full prefixes (NXX) Thousands-blocks (1,000-number pools)

The Code holder is who opened each NPA-NXX prefix — not necessarily who holds the numbers. A prefix is 10,000 numbers, but under pooling its ten 1,000-number blocks are handed out individually, often to different carriers; the code holder may hold only one block, or none. The Thousands-blocks column shows how the ten blocks are really split — click which blocks → to see who holds each 1,000-number block and its last-4-digit range. Assignments are initial assignments; the current serving carrier may differ due to portability.

Most active assignees, all time — NPA 575
QWEST CORPORATION 77
New assignments by month Sep 2026 Aug 2026 Jul 2026 Jun 2026 May 2026 Apr 2026 Mar 2026 Feb 2026 Jan 2026 Dec 2025 Nov 2025 Oct 2025
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Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
2009-07-14 575-275 not yet reported which blocks → QWEST CORPORATION 9636 DEMING NM
2008-05-07 575-674 0–9 XXXwhole prefix which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-233 6XXX7XXX8XXX · 2 holders which blocks → QWEST CORPORATION 9636 LA MESA NM
— 575-267 2XXX6XXX7XXX · 3 holders which blocks → QWEST CORPORATION 9636 HATCH NM
— 575-347 1XXX6XXX8XXX · 3 holders which blocks → QWEST CORPORATION 9636 ROSWELL NM
— 575-356 not yet reported which blocks → QWEST CORPORATION 9636 PORTALES NM
— 575-359 5XXX7XXX · 2 holders which blocks → QWEST CORPORATION 9636 PORTALES NM
— 575-373 5XXX7XXX · 2 holders which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-376 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → QWEST CORPORATION 9636 CIMARRON NM
— 575-377 5XXX8XXX · 2 holders which blocks → QWEST CORPORATION 9636 ANGEL FIRE NM
— 575-382 not yet reported which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-388 not yet reported which blocks → QWEST CORPORATION 9636 SILVERCITY NM
— 575-434 not yet reported which blocks → QWEST CORPORATION 9636 ALAMOGORDO NM
— 575-437 not yet reported which blocks → QWEST CORPORATION 9636 ALAMOGORDO NM
— 575-439 none assigned yet which blocks → QWEST CORPORATION 9636 ALAMOGORDO NM
— 575-443 none assigned yet which blocks → QWEST CORPORATION 9636 ALAMOGORDO NM
— 575-445 not yet reported which blocks → QWEST CORPORATION 9636 RATON NM
— 575-446 0XXX1XXX2XXX3XXX4XXX6XXX · 4 holders which blocks → QWEST CORPORATION 9636 ALAMOGORDO NM
— 575-461 not yet reported which blocks → QWEST CORPORATION 9636 TUCUMCARI NM
— 575-475 not yet reported which blocks → QWEST CORPORATION 9636 ALAMOGORDO NM
— 575-479 5XXX7XXX · 2 holders which blocks → QWEST CORPORATION 9636 ALAMOGORDO NM
— 575-483 1XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → QWEST CORPORATION 9636 SPRINGER NM
— 575-521 not yet reported which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-522 not yet reported which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-523 not yet reported which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-524 not yet reported which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-525 not yet reported which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-526 not yet reported which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-527 not yet reported which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-528 8XXX9XXX which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-532 not yet reported which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-534 not yet reported which blocks → QWEST CORPORATION 9636 SILVERCITY NM
— 575-537 1XXX which blocks → QWEST CORPORATION 9636 BAYARD NM
— 575-538 none assigned yet which blocks → QWEST CORPORATION 9636 SILVERCITY NM
— 575-541 3XXX which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-543 8XXX9XXX · 2 holders which blocks → QWEST CORPORATION 9636 DEMING NM
— 575-544 not yet reported which blocks → QWEST CORPORATION 9636 DEMING NM
— 575-546 not yet reported which blocks → QWEST CORPORATION 9636 DEMING NM
— 575-556 4XXX9XXX · 2 holders which blocks → QWEST CORPORATION 9636 LAS CRUCES NM
— 575-562 0XXX7XXX8XXX9XXX · 2 holders which blocks → QWEST CORPORATION 9636 PORTALES NM
— 575-572 not yet reported which blocks → QWEST CORPORATION 9636 ALAMOGORDO NM
— 575-574 none assigned yet which blocks → QWEST CORPORATION 9636 SILVERCITY NM
— 575-586 3XXX4XXX5XXX6XXX8XXX · 3 holders which blocks → QWEST CORPORATION 9636 QUESTA NM
— 575-587 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → QWEST CORPORATION 9636 PENASCO NM
— 575-589 8XXX which blocks → QWEST CORPORATION 9636 SNA TERESA NM
— 575-622 not yet reported which blocks → QWEST CORPORATION 9636 ROSWELL NM
— 575-623 not yet reported which blocks → QWEST CORPORATION 9636 ROSWELL NM
— 575-624 not yet reported which blocks → QWEST CORPORATION 9636 ROSWELL NM
— 575-625 not yet reported which blocks → QWEST CORPORATION 9636 ROSWELL NM
— 575-627 not yet reported which blocks → QWEST CORPORATION 9636 ROSWELL NM

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.