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
— 617-345 2XXX which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-346 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-347 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 QUINCY MA
— 617-348 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-349 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 CAMBRIDGE MA
— 617-350 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-351 8XXX9XXX · 2 holders which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-352 0XXX1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-353 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-354 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 CAMBRIDGE MA
— 617-355 0XXX9XXX which blocks → VERIZON NEW ENGLAND INC. 9102 BROOKLINE MA
— 617-356 0–9 XXXall 10 · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 6387 BOSTON MA
— 617-357 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-358 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-359 none assigned yet which blocks → OMNIPOINT MIAMI E LICENSE, LLC 6889 CAMBRIDGE MA
— 617-360 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX · 8 holders which blocks → VERIZON NEW ENGLAND INC. 9102 HYDE PARK MA
— 617-361 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 HYDE PARK MA
— 617-362 2XXX4XXX5XXX9XXX which blocks → BANDWIDTH.COM CLEC, LLC - MA 990E HYDE PARK MA
— 617-363 3XXX6XXX9XXX · 3 holders which blocks → VERIZON NEW ENGLAND INC. 9102 JAMAICA PL MA
— 617-364 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 HYDE PARK MA
— 617-365 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 DEDHAM MA
— 617-367 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-368 0XXX which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-369 2XXX which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-370 1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 6 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 CHELSEA MA
— 617-371 6XXX7XXX8XXX · 3 holders which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-372 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 3 holders which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-373 0XXX which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-374 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 CAMBRIDGE MA
— 617-375 9XXX which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-376 9XXX which blocks → VERIZON NEW ENGLAND INC. 9102 QUINCY MA
— 617-377 0XXX4XXX5XXX6XXX7XXX · 3 holders which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-378 1XXX2XXX5XXX7XXX8XXX which blocks → TC SYSTEMS, INC. 7135 BOSTON MA
— 617-379 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX · 3 holders which blocks → RCN TELECOM SERVICES, INC. - MA 7619 DORCHESTER MA
— 617-380 1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CHARLESTN MA
— 617-381 4XXX which blocks → VERIZON NEW ENGLAND INC. 9102 EVERETT MA
— 617-382 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 EVERETT MA
— 617-383 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 6 holders which blocks → PAETEC ITEL, LLC 829J BROOKLINE MA
— 617-384 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 CAMBRIDGE MA
— 617-385 not yet reported which blocks → TC SYSTEMS, INC. 7135 BOSTON MA
— 617-387 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 EVERETT MA
— 617-388 none assigned yet which blocks → OMNIPOINT MIAMI E LICENSE, LLC 6889 CAMBRIDGE MA
— 617-389 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 EVERETT MA
— 617-390 3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 JAMAICA PL MA
— 617-392 not yet reported which blocks → TC SYSTEMS, INC. 7135 BOSTON MA
— 617-393 5XXX6XXX7XXX · 2 holders which blocks → RCN TELECOM SERVICES, INC. - MA 7619 WATERTOWN MA
— 617-394 1XXX8XXX which blocks → VERIZON NEW ENGLAND INC. 9102 EVERETT MA
— 617-395 3XXX which blocks → LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CAMBRIDGE MA
— 617-396 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → TC SYSTEMS, INC. 7135 BROOKLINE MA
— 617-397 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders 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.