Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/21/2026

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 406
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
406-426 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 RED LODGE MT
406-427 not yet reported which blocks → RANGE TEL COOP INC 2251 SO BROADUS MT
406-428 8XXX which blocks → MID-RIVERS TEL. COOP., INC. 2246 GRASSRANGE MT
406-429 8XXX which blocks → MID-RIVERS TEL. COOP., INC. 2246 WINNETT MT
406-430 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → ONVOY, LLC - MT 453F HELENA MT
406-431 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 HELENA MT
406-432 not yet reported which blocks → NORTHERN TEL. COOP., INC. 2248 DEVON MT
406-433 not yet reported which blocks → MID-RIVERS TELEPHONE COOPERATIVE, INC. 7830 SIDNEY MT
406-434 1XXX4XXX6XXX8XXX · 4 holders which blocks → QWEST CORPORATION 9636 SHELBY MT
406-435 0XXX9XXX · 2 holders which blocks → TDS METROCOM, LLC 520K BILLINGS MT
406-436 8XXX which blocks → RANGE TEL COOP INC 2251 BROADUS MT
406-439 none assigned yet which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 HELENA MT
406-441 not yet reported which blocks → QWEST CORPORATION 9636 HELENA MT
406-442 not yet reported which blocks → QWEST CORPORATION 9636 HELENA MT
406-443 not yet reported which blocks → QWEST CORPORATION 9636 HELENA MT
406-444 not yet reported which blocks → QWEST CORPORATION 9636 HELENA MT
406-445 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → QWEST CORPORATION 9636 RED LODGE MT
406-446 6XXX7XXX8XXX which blocks → QWEST CORPORATION 9636 RED LODGE MT
406-447 0XXX which blocks → QWEST CORPORATION 9636 HELENA MT
406-448 8XXX which blocks → NEMONT TEL COOP INC 2247 NO POPLAR MT
406-449 not yet reported which blocks → QWEST CORPORATION 9636 HELENA MT
406-450 none assigned yet which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 SHELBY MT
406-452 not yet reported which blocks → QWEST CORPORATION 9636 GREATFALLS MT
406-453 not yet reported which blocks → QWEST CORPORATION 9636 GREATFALLS MT
406-454 not yet reported which blocks → QWEST CORPORATION 9636 GREATFALLS MT
406-455 none assigned yet which blocks → QWEST CORPORATION 9636 GREATFALLS MT
406-456 not yet reported which blocks → TRIANGLE TEL. COOP. ASSN., INC. 2257 SO CHESTER MT
406-457 6XXX which blocks → QWEST CORPORATION 9636 HELENA MT
406-458 none assigned yet which blocks → QWEST CORPORATION 9636 HELENA MT
406-459 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 HELENA MT
406-460 5XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 SHELBY MT
406-461 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 HELENA MT
406-462 not yet reported which blocks → TRIANGLE TEL. COOP. ASSN., INC. 2257 WINIFRED MT
406-463 not yet reported which blocks → 3 RIVERS TEL. COOP., INC. 2255 POWER MT
406-464 4XXX6XXX · 2 holders which blocks → MID-RIVERS TEL. COOP., INC. 2246 ROY MT
406-465 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 HELENA MT
406-466 7XXX which blocks → 3 RIVERS TEL. COOP., INC. 2255 CHOTEAU MT
406-467 0XXX which blocks → 3 RIVERS TEL. COOP., INC. 2255 FAIRFIELD MT
406-468 1XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → QWEST CORPORATION 9636 CASCADE MT
406-469 not yet reported which blocks → 3 RIVERS TEL. COOP., INC. 2255 PENDROY MT
406-470 1XXX2XXX4XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 SHELBY MT
406-472 not yet reported which blocks → 3 RIVERS TEL. COOP., INC. 2255 DUPUYER MT
406-473 not yet reported which blocks → TRIANGLE TEL. COOP. ASSN., INC. 3310 JUDITH GAP MT
406-474 not yet reported which blocks → NEMONT TEL COOP INC 2247 FLAXVILLE MT
406-475 0XXX1XXX2XXX4XXX5XXX6XXX7XXX · 2 holders which blocks → QWEST CORPORATION 9636 HELENA MT
406-476 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → QWEST CORPORATION 9636 DUTTON MT
406-477 1XXX which blocks → RANGE TEL COOP INC 2251 LAME DEER MT
406-478 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 SIDNEY MT
406-480 6XXX7XXX8XXX · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 6564 SIDNEY MT
406-482 0XXX5XXX which blocks → QWEST CORPORATION 9636 SIDNEY MT

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/21/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.