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
— 603-528 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 LACONIA NH
— 603-529 not yet reported which blocks → GRANITE STATE TEL., INC. 0039 WEARE NH
— 603-531 2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 PORTSMOUTH NH
— 603-532 0XXX3XXX · 2 holders which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 JAFFREY NH
— 603-533 none assigned yet which blocks → UNITED STATES CELLULAR - NH 6290 MERRIMACK NH
— 603-534 not yet reported which blocks → BELL ATLANTIC MOBILE, INC 6386 DOVER NH
— 603-535 not yet reported which blocks → PAETEC ITEL, LLC 829J PLYMOUTH NH
— 603-536 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 PLYMOUTH NH
— 603-537 4XXX6XXX8XXX · 3 holders which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 DERRY NH
— 603-538 0XXX3XXX · 2 holders which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 PITTSBURG NH
— 603-539 none assigned yet which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 CTROSSIPEE NH
— 603-542 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 CLAREMONT NH
— 603-543 none assigned yet which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 CLAREMONT NH
— 603-544 4XXX5XXX · 2 holders which blocks → MERRIMACK CO. TELEPHONE CO., DBA CONTOOCOOK VALLEY 3320 MELVIN VLG NH
— 603-545 1XXX2XXX4XXX5XXX7XXX8XXX9XXX which blocks → PAETEC ITEL, LLC 829J CONCORD NH
— 603-546 3XXX4XXX5XXX7XXX8XXX · 4 holders which blocks → PAETEC ITEL, LLC 829J NASHUA NH
— 603-547 0XXX1XXX4XXX5XXX7XXX9XXX · 4 holders which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 GREENFIELD NH
— 603-548 not yet reported which blocks → BELL ATLANTIC MOBILE, INC 6386 DERRY NH
— 603-549 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 DERRY NH
— 603-550 0–9 XXXall 10 · 5 holders which blocks → TELNYX LLC 073H DOVER NH
— 603-551 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 MANCHESTER NH
— 603-552 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 7778 DERRY NH
— 603-553 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 DERRY NH
— 603-554 0XXX1XXX2XXX3XXX8XXX9XXX · 4 holders which blocks → UNITED STATES CELLULAR - NH 6290 MILFORD NH
— 603-555 not yet reported which blocks → MULTIPLE OCN LISTING MULT DIR ASST NH
— 603-556 0XXX1XXX2XXX3XXX5XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - NH 4017 LACONIA NH
— 603-557 none assigned yet which blocks → OMNIPOINT MIAMI E LICENSE, LLC 6889 NASHUA NH
— 603-558 6XXX7XXX9XXX which blocks → BELL ATLANTIC MOBILE, INC 6386 CLAREMONT NH
— 603-559 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 PORTSMOUTH NH
— 603-560 9XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 SALEM NH
— 603-561 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 NASHUA NH
— 603-562 0XXX1XXX2XXX4XXX which blocks → UNITED STATES CELLULAR - NH 6290 PETERBROGH NH
— 603-563 0XXX1XXX3XXX5XXX · 4 holders which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 DUBLIN NH
— 603-564 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 MANCHESTER NH
— 603-565 0XXX1XXX2XXX3XXX5XXX6XXX9XXX · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - NH 4017 PENACOOK NH
— 603-566 not yet reported which blocks → BELL ATLANTIC MOBILE, INC 6386 NASHUA NH
— 603-567 0XXX7XXX8XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - NH 4017 PETERBROGH NH
— 603-569 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 WOLFEBORO NH
— 603-570 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - NH 8299 PORTSMOUTH NH
— 603-571 2XXX3XXX4XXX6XXX9XXX · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 DERRY NH
— 603-573 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 7778 CONCORD NH
— 603-574 0XXX which blocks → LEVEL 3 COMMUNICATIONS, LLC - NH 4017 ALSTEAD NH
— 603-575 0XXX1XXX3XXX5XXX6XXX7XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 7778 LITTLETON NH
— 603-576 2XXX which blocks → LEVEL 3 COMMUNICATIONS, LLC - NH 4017 ORFORD NH
— 603-577 0XXX1XXX · 2 holders which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 NASHUA NH
— 603-578 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 NASHUA NH
— 603-579 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 NASHUA NH
— 603-580 0XXX3XXX4XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → COMCAST IP PHONE, LLC 318J EXETER NH
— 603-581 1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J LACONIA NH
— 603-582 none assigned yet which blocks → UNITED STATES CELLULAR - NH 6290 MERRIMACK NH

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.