NumberResearch Membership · Data 09/19/2026

Recent prefix assignments

1 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, last 30 days — NPA 508
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 1
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
— 508-572 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 BILLERICA MA
— 508-573 0–9 XXXall 10 · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 MARLBORO MA
— 508-574 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 BILLERICA MA
— 508-576 0XXX1XXX2XXX3XXX4XXX5XXX8XXX9XXX · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MA 4018 NO ATTLEBO MA
— 508-577 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 BROCKTON MA
— 508-578 not yet reported which blocks → BANDWIDTH.COM CLEC, LLC - MA 990E DOVER MA
— 508-579 none assigned yet which blocks → METROPCS, INC. 5562 WORCESTER MA
— 508-580 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BROCKTON MA
— 508-581 0XXX2XXX3XXX4XXX5XXX6XXX7XXX · 4 holders which blocks → VERIZON NEW ENGLAND INC. 9102 MILLBURY MA
— 508-582 not yet reported which blocks → NORFOLK COUNTY INTERNET, INC. 6083 HYANNIS MA
— 508-583 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BROCKTON MA
— 508-584 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BROCKTON MA
— 508-585 not yet reported which blocks → NORFOLK COUNTY INTERNET, INC. 6083 BRIDGEWTR MA
— 508-586 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BROCKTON MA
— 508-587 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BROCKTON MA
— 508-588 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 BROCKTON MA
— 508-589 1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 HOPKINTON MA
— 508-590 3XXX9XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 FRANKLIN MA
— 508-591 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → TC SYSTEMS, INC. 7135 PLYMOUTH MA
— 508-592 0XXX which blocks → VERIZON NEW ENGLAND INC. 9102 FRAMINGHAM MA
— 508-593 0XXX1XXX2XXX3XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MA 4018 CHATHAM MA
— 508-594 0XXX3XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → TC SYSTEMS, INC. 7135 MANSFIELD MA
— 508-595 4XXX6XXX8XXX · 3 holders which blocks → VERIZON NEW ENGLAND INC. 9102 WORCESTER MA
— 508-596 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 FRAMINGHAM MA
— 508-597 5XXX6XXX7XXX8XXX9XXX which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 MARLBORO MA
— 508-598 0XXX2XXX3XXX5XXX7XXX8XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 FRAMINGHAM MA
— 508-599 0XXX3XXX4XXX5XXX8XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WESTBORO MA
— 508-601 not yet reported which blocks → MA
— 508-602 not yet reported which blocks → MA
— 508-604 not yet reported which blocks → MA
— 508-605 not yet reported which blocks → MA
— 508-606 not yet reported which blocks → MA
— 508-607 not yet reported which blocks → MA
— 508-608 not yet reported which blocks → MA
— 508-609 not yet reported which blocks → MA
— 508-610 not yet reported which blocks → MA
— 508-611 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MA
— 508-612 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 6387 WORCESTER MA
— 508-613 1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MA 4018 FRANKLIN MA
— 508-614 0XXX2XXX5XXX8XXX9XXX · 3 holders which blocks → AT&T - LOCAL 7421 WESTBORO MA
— 508-615 not yet reported which blocks → OMNIPOINT MIAMI E LICENSE, LLC 6889 WORCESTER MA
— 508-616 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 WESTBORO MA
— 508-618 1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 MANSFIELD MA
— 508-619 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MA 4018 DENNIS MA
— 508-620 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 FRAMINGHAM MA
— 508-621 6XXX7XXX8XXX9XXX · 3 holders which blocks → TC SYSTEMS, INC. 7135 WESTBORO MA
— 508-622 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → COMCAST IP PHONE, LLC 318J NORTON MA
— 508-623 5XXX6XXX7XXX8XXX9XXX which blocks → PAETEC ITEL, LLC 829J FOXBORO MA
— 508-624 not yet reported which blocks → VERIZON NEW ENGLAND INC. 9102 MARLBORO MA
— 508-625 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → COMCAST IP PHONE, LLC 318J HOPKINTON MA

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.