NumberResearch Membership · Data 09/30/2026

Recent prefix assignments

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

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
Rogers Communications Canada Inc. (Wireless) 46
8X8, INC. 43
NEW CINGULAR WIRELESS PCS, LLC - DC 28
NEW CINGULAR WIRELESS PCS, LLC - IL 23
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
— 443-320 0XXX3XXX6XXX7XXX8XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BALTIMORE MD
— 443-321 not yet reported which blocks → PAETEC ITEL, LLC 829J ANNAPOLIS MD
— 443-323 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → PAETEC ITEL, LLC 829J SHARPTOWN MD
— 443-324 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 BALTIMORE MD
— 443-325 2XXX3XXX4XXX5XXX6XXX · 2 holders which blocks → PAETEC ITEL, LLC 829J ELLICOTTCY MD
— 443-327 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → PAETEC ITEL, LLC 829J ABERDEEN MD
— 443-328 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → PAETEC ITEL, LLC 829J SYKESVILLE MD
— 443-329 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 WATERLO236 MD
— 443-330 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → PAETEC ITEL, LLC 829J COCKEYSVL MD
— 443-331 0XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 5 holders which blocks → PAETEC ITEL, LLC 829J TANEYTOWN MD
— 443-335 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → METROPCS, INC. 5562 BRYNPKLNCM MD
— 443-336 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 ANNAPOLIS MD
— 443-337 0–9 XXXall 10 · 2 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 SPARROWSPT MD
— 443-338 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → PAETEC ITEL, LLC 829J SPARKSGLNC MD
— 443-339 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → PAETEC ITEL, LLC 829J SHERWD FOR MD
— 443-340 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WESTMINSTR MD
— 443-341 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 CATONSVL MD
— 443-342 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → PAETEC ITEL, LLC 829J SOLOMONS MD
— 443-343 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 MILLERSVL MD
— 443-344 not yet reported which blocks → CORE COMMUNICATIONS, INC.- MD 2593 SEVERNA PK MD
— 443-345 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ABERDEEN MD
— 443-346 0–9 XXXall 10 · 3 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 SEVERNA PK MD
— 443-347 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → PAETEC ITEL, LLC 829J CARDIFF MD
— 443-348 0XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 WOODLAWN MD
— 443-349 not yet reported which blocks → CORE COMMUNICATIONS, INC.- MD 2593 SILVER RUN MD
— 443-350 8XXX9XXX · 2 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 ELKTON MD
— 443-351 4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J ODENTON MD
— 443-352 0XXX1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 PIKESVILLE MD
— 443-354 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 GLENBURNIE MD
— 443-355 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 ELLICOTTCY MD
— 443-356 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BEL AIR MD
— 443-357 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → VERIZON MARYLAND, INC. 9212 PIKESVILLE MD
— 443-359 4XXX5XXX6XXX7XXX · 2 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 DELMAR MD
— 443-360 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 ABERDEEN MD
— 443-361 not yet reported which blocks → CORE COMMUNICATIONS, INC.- MD 2593 SYKESVILLE MD
— 443-362 1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 EASTON MD
— 443-363 0–9 XXXall 10 · 4 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 SEVERN MD
— 443-364 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 ELLICOTTCY MD
— 443-365 2XXX3XXX4XXX5XXX7XXX8XXX · 3 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 SALISBURY MD
— 443-367 1XXX4XXX6XXX8XXX9XXX · 5 holders which blocks → VERIZON MARYLAND, INC. 9212 COLUMBIA MD
— 443-368 not yet reported which blocks → CORE COMMUNICATIONS, INC.- MD 2593 WESTMINSTR MD
— 443-369 not yet reported which blocks → CORE COMMUNICATIONS, INC.- MD 2593 BEL AIR MD
— 443-370 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 ANNAPOLIS MD
— 443-371 0–9 XXXall 10 · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 BEL AIR MD
— 443-373 0XXX2XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → METROPCS, INC. 5562 OCEAN CITY MD
— 443-374 1XXX2XXX5XXX7XXX8XXX which blocks → PAETEC ITEL, LLC 829J ABERDEEN MD
— 443-375 3XXX4XXX5XXX · 3 holders which blocks → METROPCS, INC. 5562 HAMPSTEAD MD
— 443-376 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 DUNDALK MD
— 443-380 0–9 XXXall 10 · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 WOODLAWN MD
— 443-381 0–9 XXXall 10 · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 REISTERSTN MD

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/30/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.