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 443
PAETEC ITEL, LLC 153
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 121
OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 94
NEW CINGULAR WIRELESS PCS, LLC - DC 71
LEVEL 3 COMMUNICATIONS, LLC - MD 69
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
— 443-457 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 BRYNPKLNCM MD
— 443-458 2XXX3XXX5XXX8XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 ANNAPOLIS MD
— 443-459 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → PAETEC ITEL, LLC 829J ELKRIDGE MD
— 443-460 5XXX8XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 ESSEX MD
— 443-461 4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J PARKVILLE MD
— 443-463 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 BALTIMORE MD
— 443-465 2XXX3XXX7XXX8XXX9XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 TOWSON MD
— 443-466 2XXX which blocks → METROPCS, INC. 5562 ELKTON MD
— 443-471 6XXX8XXX9XXX · 2 holders which blocks → PAETEC ITEL, LLC 829J PIKESVILLE MD
— 443-472 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 COLUMBIA MD
— 443-474 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 CATONSVL MD
— 443-476 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
— 443-479 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WATERLO236 MD
— 443-480 5XXX7XXX8XXX · 2 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 CHESTERTN MD
— 443-481 0XXX2XXX7XXX8XXX9XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J ANNAPOLIS MD
— 443-482 5XXX6XXX which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
— 443-483 0–9 XXXall 10 · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 CARDIFF MD
— 443-484 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 EDGEWOOD MD
— 443-485 0–9 XXXall 10 · 8 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ELKTON MD
— 443-486 0–9 XXXall 10 · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 PRINCEFRCK MD
— 443-487 0–9 XXXall 10 · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 WESTMINSTR MD
— 443-489 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 7 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 CHASE MD
— 443-490 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → BANDWIDTH.COM CLEC, LLC - MD 071F EDGEWOOD MD
— 443-491 2XXX3XXX7XXX8XXX9XXX · 5 holders which blocks → ONVOY, LLC - MD 876D PARKTON MD
— 443-492 2XXX3XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ELKRIDGE MD
— 443-494 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → BANDWIDTH.COM CLEC, LLC - MD 071F MILLERSVL MD
— 443-495 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → BANDWIDTH.COM CLEC, LLC - MD 071F PARKVILLE MD
— 443-496 3XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → METROPCS, INC. 5562 EASTON MD
— 443-497 5XXX7XXX8XXX9XXX · 2 holders which blocks → METROPCS, INC. 5562 SALISBURY MD
— 443-498 3XXX6XXX7XXX8XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 CATONSVL MD
— 443-499 2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → BANDWIDTH.COM CLEC, LLC - MD 071F JARRETTSVL MD
— 443-501 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 PIKESVILLE MD
— 443-502 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 HAVREGRACE MD
— 443-503 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 DUNDALK MD
— 443-504 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J FALLSTON MD
— 443-505 0–9 XXXall 10 · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ESSEX MD
— 443-506 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 BALTIMORE MD
— 443-507 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 7 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 HAMPSTEAD MD
— 443-508 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 8 holders which blocks → PAETEC ITEL, LLC 829J HAMPSTEAD MD
— 443-511 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MD
— 443-512 1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 EDGEWOOD MD
— 443-513 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 BERLIN MD
— 443-514 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J CATONSVL MD
— 443-516 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → ONVOY, LLC - MD 876D SYKESVILLE MD
— 443-517 0–9 XXXall 10 · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 GLENBURNIE MD
— 443-519 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 TOWSON MD
— 443-520 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 CATONSVL MD
— 443-521 8XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 CAMBRIDGE MD
— 443-522 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J REISTERSTN MD
— 443-523 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 SALISBURY MD

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.