NumberResearch Membership · Data 09/19/2026

Recent prefix assignments

0 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, 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
Clear Download CSV ↓
Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
— 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
— 443-382 not yet reported which blocks → CORE COMMUNICATIONS, INC.- MD 2593 CAMBRIDGE MD
— 443-383 0XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 3 holders which blocks → PAETEC ITEL, LLC 829J SILVER RUN MD

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.