NumberResearch Membership · Data 09/20/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/20/2026

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 617
VERIZON NEW ENGLAND INC. 334
MCIMETRO ACCESS TRANSMISSION SERVICES LLC 71
NEW CINGULAR WIRELESS PCS, LLC - DC 68
PAETEC ITEL, LLC 44
TC SYSTEMS, INC. 41
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
— 617-561 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 EASTBOSTON MA
— 617-562 8XXX which blocks → VERIZON NEW ENGLAND INC. 9102 BRIGHTON MA
— 617-563 not yet reported which blocks → TC SYSTEMS, INC. 7135 BOSTON MA
— 617-564 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → PAETEC ITEL, LLC 829J NEWTON MA
— 617-565 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-566 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BROOKLINE MA
— 617-567 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 EASTBOSTON MA
— 617-568 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 EASTBOSTON MA
— 617-569 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 EASTBOSTON MA
— 617-570 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-571 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 6387 BOSTON MA
— 617-572 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-573 0XXX which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-574 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-575 2XXX7XXX9XXX · 2 holders which blocks → VERIZON NEW ENGLAND INC. 9102 CAMBRIDGE MA
— 617-576 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 CAMBRIDGE MA
— 617-577 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 CAMBRIDGE MA
— 617-578 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-579 6XXX7XXX8XXX · 2 holders which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-580 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 CHARLESTN MA
— 617-581 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J NEWTON MA
— 617-582 2XXX3XXX · 2 holders which blocks → VERIZON NEW ENGLAND INC. 9102 BROOKLINE MA
— 617-583 0XXX2XXX3XXX7XXX9XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CAMBRIDGE MA
— 617-584 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 NEWTON MA
— 617-585 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-586 1XXX5XXX6XXX7XXX9XXX · 3 holders which blocks → BANDWIDTH.COM CLEC, LLC - MA 990E BRIGHTON MA
— 617-587 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-588 not yet reported which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 CAMBRIDGE MA
— 617-589 1XXX5XXX8XXX · 3 holders which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-590 none assigned yet which blocks → METROPCS, INC. 5562 BOSTON MA
— 617-591 5XXX which blocks → VERIZON NEW ENGLAND INC. 9102 SOMERVILLE MA
— 617-592 none assigned yet which blocks → METROPCS, INC. 5562 BOSTON MA
— 617-593 none assigned yet which blocks → METROPCS, INC. 5562 BOSTON MA
— 617-594 none assigned yet which blocks → METROPCS, INC. 5562 BOSTON MA
— 617-596 none assigned yet which blocks → METROPCS, INC. 5562 SO BOSTON MA
— 617-597 3XXX7XXX8XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 NEWTON MA
— 617-598 not yet reported which blocks → TC SYSTEMS, INC. 7135 BOSTON MA
— 617-600 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WATERTOWN MA
— 617-601 not yet reported which blocks → NORFOLK COUNTY INTERNET, INC. 6083 EVERETT MA
— 617-602 0–9 XXXall 10 · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 ROXBURY MA
— 617-603 not yet reported which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 BOSTON MA
— 617-604 1XXX2XXX3XXX4XXX5XXX6XXX9XXX · 2 holders which blocks → VERIZON NEW ENGLAND INC. 9102 HYDE PARK MA
— 617-605 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 MALDEN MA
— 617-606 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MA 4018 ROXBURY MA
— 617-607 3XXX4XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WATERTOWN MA
— 617-608 3XXX7XXX8XXX9XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 BROOKLINE MA
— 617-610 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 NEWTON MA
— 617-611 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MA
— 617-612 0XXX3XXX4XXX5XXX6XXX8XXX · 5 holders which blocks → TC SYSTEMS, INC. 7135 WATERTOWN MA
— 617-613 not yet reported which blocks → TC SYSTEMS, INC. 7135 CAMBRIDGE MA

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.