NumberResearch Membership · Data 09/19/2026

Recent prefix assignments

355 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/19/2026

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. 38
ONVOY, LLC - CA 31
NEW CINGULAR WIRELESS PCS, LLC - IL 28
NEW CINGULAR WIRELESS PCS, LLC - DC 26
ONVOY, LLC - NJ 18
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
— 734-370 not yet reported which blocks → TELNET WORLDWIDE, INC. 817J LAMBERTVL MI
— 734-372 not yet reported which blocks → TELNET WORLDWIDE, INC. 817J ANN ARBOR MI
— 734-374 6XXX which blocks → MICHIGAN BELL TEL CO 9323 WYANDOTTE MI
— 734-375 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 8 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E GREGORY MI
— 734-376 not yet reported which blocks → TELNET WORLDWIDE, INC. 817J IDA MI
— 734-377 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2964 WAYNE MI
— 734-378 1XXX2XXX3XXX6XXX7XXX8XXX9XXX which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 7279 DEXTER MI
— 734-379 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 ROCKWOOD MI
— 734-380 not yet reported which blocks → SPOK, INC. 6630 ROMULUS MI
— 734-382 0–9 XXXall 10 · 4 holders which blocks → PAETEC ITEL, LLC 829J GREGORY MI
— 734-383 7XXX which blocks → OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2964 YPSILANTI MI
— 734-384 3XXX which blocks → MICHIGAN BELL TEL CO 9323 MONROE MI
— 734-385 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX · 5 holders which blocks → PAETEC ITEL, LLC 829J CHELSEA MI
— 734-387 not yet reported which blocks → TELNET WORLDWIDE, INC. 817J TEMPERANCE MI
— 734-389 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J ANN ARBOR MI
— 734-390 4XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → PAETEC ITEL, LLC 829J YPSILANTI MI
— 734-391 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 8 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E BELLEVILLE MI
— 734-392 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E PLYMOUTH MI
— 734-393 0–9 XXXall 10 · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MI 6120 LOSTPNNSUL MI
— 734-394 6XXX7XXX8XXX9XXX · 2 holders which blocks → MICHIGAN BELL TEL CO 9323 WAYNE MI
— 734-395 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 ANN ARBOR MI
— 734-396 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E MANCHESTER MI
— 734-397 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 WAYNE MI
— 734-398 1XXX2XXX3XXX4XXX · 3 holders which blocks → MICHIGAN BELL TEL CO 9323 WAYNE MI
— 734-399 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MI 770E MAYBEE MI
— 734-401 not yet reported which blocks → TELNET WORLDWIDE, INC. 817J SALINE MI
— 734-402 7XXX8XXX9XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J LIVONIA MI
— 734-403 1XXX3XXX4XXX5XXX6XXX8XXX9XXX · 5 holders which blocks → PAETEC ITEL, LLC 829J ROMULUS MI
— 734-404 4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → PAETEC ITEL, LLC 829J PLYMOUTH MI
— 734-405 3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → PAETEC ITEL, LLC 829J WAYNE MI
— 734-407 1XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → PAETEC ITEL, LLC 829J WYANDOTTE MI
— 734-408 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 5 holders which blocks → PAETEC ITEL, LLC 829J DEXTER MI
— 734-411 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MI
— 734-413 0XXX1XXX2XXX3XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 7279 ROMULUS MI
— 734-414 2XXX which blocks → MICHIGAN BELL TEL CO 9323 PLYMOUTH MI
— 734-415 1XXX2XXX3XXX4XXX6XXX8XXX9XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J NEW BOSTON MI
— 734-416 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 PLYMOUTH MI
— 734-417 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 6003 ANN ARBOR MI
— 734-419 1XXX3XXX4XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 7279 WAYNE MI
— 734-420 8XXX which blocks → MICHIGAN BELL TEL CO 9323 PLYMOUTH MI
— 734-421 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 LIVONIA MI
— 734-422 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 LIVONIA MI
— 734-423 7XXX8XXX9XXX which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 7279 WAYNE MI
— 734-424 5XXX6XXX7XXX8XXX · 4 holders which blocks → MICHIGAN BELL TEL CO 9323 DEXTER MI
— 734-425 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 LIVONIA MI
— 734-426 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 DEXTER MI
— 734-427 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 LIVONIA MI
— 734-428 3XXX6XXX · 2 holders which blocks → MICHIGAN BELL TEL CO 9323 MANCHESTER MI
— 734-429 not yet reported which blocks → FRONTIER NORTH, INC. - MI 0695 SALINE MI
— 734-432 not yet reported which blocks → MICHIGAN BELL TEL CO 9323 LIVONIA MI

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.