NumberResearch Membership · Data 09/19/2026

Recent prefix assignments

0 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, all time — NPA 603
CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 247
BELL ATLANTIC MOBILE, INC 74
PAETEC ITEL, LLC 58
MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 44
COMCAST IP PHONE, LLC 40
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
— 603-550 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 0XXX1XXX2XXX3XXX5XXX9XXX · 6 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
— 603-583 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - NH 4017 EXETER NH
— 603-585 0XXX1XXX4XXX5XXX · 3 holders which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 FITZWILLIM NH
— 603-586 0XXX5XXX6XXX9XXX · 3 holders which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 JEFFERSON NH
— 603-587 0XXX1XXX2XXX3XXX4XXX7XXX8XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 7778 CANDIA NH
— 603-588 5XXX which blocks → MERRIMACK CO. TELEPHONE CO., DBA CONTOOCOOK VALLEY 3320 ANTRIM NH
— 603-589 5XXX7XXX9XXX · 2 holders which blocks → PAETEC ITEL, LLC 829J NASHUA NH
— 603-590 3XXX which blocks → FREEDOM RING COMMUNICATIONS, LLC 8468 DURHAM NH
— 603-591 9XXX which blocks → OMNIPOINT MIAMI E LICENSE, LLC 6889 MANCHESTER NH
— 603-592 1XXX4XXX5XXX8XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 7778 SPOFFORD NH
— 603-594 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 NASHUA NH
— 603-595 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 NASHUA NH
— 603-596 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 NASHUA NH
— 603-597 1XXX6XXX8XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 7778 LYME NH
— 603-598 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 NASHUA NH
— 603-599 not yet reported which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 NASHUA NH
— 603-601 0–9 XXXall 10 · 5 holders which blocks → PAETEC ITEL, LLC 829J HAMPTON NH
— 603-604 0XXX4XXX6XXX · 3 holders which blocks → CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 5113 RYE BEACH NH
— 603-605 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → PEERLESS NETWORK OF NEW HAMPSHIRE, LLC - NH 927H DOVER NH
— 603-606 0XXX1XXX2XXX3XXX4XXX7XXX8XXX9XXX · 4 holders which blocks → ONVOY SPECTRUM, LLC 624H MANCHESTER NH

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.