NumberResearch Membership · Data 09/27/2026

Recent prefix assignments

334 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/27/2026

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 26
Rogers Communications Canada Inc. (Wireless) 23
NEW CINGULAR WIRELESS PCS, LLC - IL 22
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
— 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
— 617-614 5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 NEWTON MA
— 617-615 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → RCN TELECOM SERVICES, INC. - MA 7619 MILTON MA
— 617-616 0XXX2XXX3XXX5XXX8XXX9XXX · 5 holders which blocks → TC SYSTEMS, INC. 7135 SOMERVILLE MA
— 617-618 3XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 NEWTON MA
— 617-619 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA
— 617-620 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 6387 BOSTON MA
— 617-621 4XXX which blocks → VERIZON NEW ENGLAND INC. 9102 CAMBRIDGE MA
— 617-622 3XXX4XXX5XXX6XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MA 4018 SO BOSTON MA
— 617-623 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 SOMERVILLE MA
— 617-624 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BOSTON MA

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/27/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.