NumberResearch Membership · Data 09/29/2026

Recent prefix assignments

347 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/29/2026

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, last 30 days
8X8, INC. 43
NEW CINGULAR WIRELESS PCS, LLC - DC 28
Rogers Communications Canada Inc. (Wireless) 23
NEW CINGULAR WIRELESS PCS, LLC - IL 23
ONVOY, LLC - CA 19
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
— 406-578 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → QWEST CORPORATION 9636 WILSALL MT
— 406-579 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 BOZEMAN MT
— 406-580 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 BOZEMAN MT
— 406-581 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 BOZEMAN MT
— 406-582 not yet reported which blocks → QWEST CORPORATION 9636 BOZEMAN MT
— 406-583 not yet reported which blocks → MID-RIVERS TEL. COOP., INC. 2246 BLOOMFIELD MT
— 406-584 none assigned yet which blocks → MID-RIVERS TEL. COOP., INC. 2246 LINDSAY MT
— 406-585 not yet reported which blocks → QWEST CORPORATION 9636 BOZEMAN MT
— 406-586 not yet reported which blocks → QWEST CORPORATION 9636 BOZEMAN MT
— 406-587 not yet reported which blocks → QWEST CORPORATION 9636 BOZEMAN MT
— 406-588 not yet reported which blocks → MID-RIVERS TEL. COOP., INC. 2246 CARLYLE MT
— 406-589 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 BOZEMAN MT
— 406-590 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 GREATFALLS MT
— 406-591 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 BILLINGS MT
— 406-592 none assigned yet which blocks → RANGE TEL COOP INC 2251 BUSBY MT
— 406-593 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 BUTTE MT
— 406-594 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 HELENA MT
— 406-595 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 BOZEMAN MT
— 406-596 none assigned yet which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 DILLON MT
— 406-597 6XXX8XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 SHELBY MT
— 406-598 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 BILLINGS MT
— 406-611 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MT
— 406-621 0XXX1XXX2XXX5XXX · 2 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 FORTBENTON MT
— 406-622 8XXX9XXX · 2 holders which blocks → TRIANGLE TEL. COOP. ASSN., INC. 3310 FORTBENTON MT
— 406-623 0–9 XXXall 10 · 8 holders which blocks → COMMIO, LLC 939H HARDIN MT
— 406-625 0–9 XXXall 10 · 6 holders which blocks → AT&T - LOCAL 7421 STEVENSVL MT
— 406-626 3XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → QWEST CORPORATION 9636 FRENCHTOWN MT
— 406-627 not yet reported which blocks → 3 RIVERS TEL. COOP., INC. 2255 EASTCONRAD MT
— 406-628 0XXX which blocks → QWEST CORPORATION 9636 LAUREL MT
— 406-629 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → ONVOY, LLC - MT 453F HARDIN MT
— 406-632 8XXX which blocks → TRIANGLE TEL. COOP. ASSN., INC. 3310 HARLOWTON MT
— 406-633 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → QWEST CORPORATION 9636 LAUREL MT
— 406-634 3XXX4XXX5XXX · 2 holders which blocks → ONVOY, LLC - MT 453F HELENA MT
— 406-635 0XXX1XXX2XXX3XXX6XXX7XXX8XXX · 5 holders which blocks → MID-RIVERS TEL. COOP., INC. 2246 TERRY MT
— 406-636 not yet reported which blocks → MID-RIVERS TEL. COOP., INC. 2246 LAVINA MT
— 406-637 3XXX4XXX6XXX7XXX8XXX · 3 holders which blocks → QWEST CORPORATION 9636 TERRY MT
— 406-638 0XXX1XXX5XXX6XXX8XXX · 4 holders which blocks → PROJECT TEL. CO., INC. 2250 HARDIN MT
— 406-639 not yet reported which blocks → PROJECT TEL. CO., INC. 2250 LODGEGRASS MT
— 406-640 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 WYELLOWSTN MT
— 406-641 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 WYELLOWSTN MT
— 406-642 0XXX4XXX5XXX7XXX8XXX · 2 holders which blocks → QWEST CORPORATION 9636 VICTOR MT
— 406-644 0XXX1XXX4XXX · 2 holders which blocks → BLACKFOOT TEL. COOP., INC. 2235 CHARLO MT
— 406-645 2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → ONVOY, LLC - MT 453F DEER LODGE MT
— 406-646 2XXX3XXX6XXX8XXX · 3 holders which blocks → QWEST CORPORATION 9636 WYELLOWSTN MT
— 406-648 none assigned yet which blocks → NEMONT TEL COOP INC 2247 NOHINSDALE MT
— 406-649 0XXX1XXX which blocks → BLACKFOOT TEL. COOP., INC. 2235 ST REGIS MT
— 406-650 not yet reported which blocks → SAGEBRUSH CELLULAR, INC. 443B WOLF POINT MT
— 406-651 7XXX which blocks → QWEST CORPORATION 9636 BILLINGS MT
— 406-652 not yet reported which blocks → QWEST CORPORATION 9636 BILLINGS MT
— 406-653 none assigned yet which blocks → NEMONT TEL COOP INC 2247 WOLF POINT MT

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/29/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.