NumberResearch Membership · Data 09/19/2026

Recent prefix assignments

4 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 667
NEW CINGULAR WIRELESS PCS, LLC - DC 2
ONVOY, LLC - MD 1
METROPCS, INC. 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
2018-06-12 667-246 0–9 XXXwhole prefix which blocks → CORE COMMUNICATIONS, INC.- MD 2593 CENTREVL MD
2018-06-12 667-247 0–9 XXXall 10 · 2 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 CHESAPKECY MD
2018-06-12 667-248 0–9 XXXall 10 · 2 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 DENTON MD
2018-06-12 667-249 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 GALENA MD
2018-06-11 667-236 0–9 XXXall 10 · 2 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 PERRYVILLE MD
2018-06-11 667-237 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 WEST RIVER MD
2018-06-04 667-243 0–9 XXXall 10 · 2 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 OXFORD MD
2018-06-04 667-345 0–9 XXXall 10 · 5 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 CATONSVL MD
2018-06-04 667-364 0–9 XXXall 10 · 3 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 STEVENSVL MD
2018-06-04 667-866 0–9 XXXall 10 · 3 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 DARLINGTON MD
2018-06-01 667-235 0–9 XXXall 10 · 4 holders which blocks → VONAGE AMERICA LLC 197D SALISBURY MD
2018-06-01 667-300 0–9 XXXall 10 · 3 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 COLUMBIA MD
2018-06-01 667-336 0–9 XXXall 10 · 3 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 BEL AIR MD
2018-06-01 667-500 0–9 XXXall 10 · 2 holders which blocks → CORE COMMUNICATIONS, INC.- MD 2593 ANNAPOLIS MD
2018-05-31 667-277 0–9 XXXwhole prefix which blocks → CORE COMMUNICATIONS, INC.- MD 2593 SHERWD FOR MD
2018-04-04 667-232 0–9 XXXall 10 · 5 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 GLENBURNIE MD
2018-03-09 667-868 0XXX1XXX2XXX3XXX4XXX7XXX · 4 holders which blocks → CHARTER IP ENABLED SERVICES, LLC 792K CRISFIELD MD
2018-02-13 667-230 0–9 XXXall 10 · 4 holders which blocks → PEERLESS NETWORK OF MARYLAND, LLC 568G CENTREVL MD
2017-09-15 667-227 0–9 XXXall 10 · 5 holders which blocks → ATLANTECH ONLINE, INC. - MD 361H SALISBURY MD
2017-08-04 667-223 0–9 XXXall 10 · 2 holders which blocks → VONAGE AMERICA LLC 197D BALTIMORE MD
2017-06-20 667-266 0–9 XXXall 10 · 4 holders which blocks → COMMIO, LLC 939H SALISBURY MD
2017-06-20 667-867 0–9 XXXall 10 · 3 holders which blocks → COMMIO, LLC 939H BALTIMORE MD
2017-06-14 667-221 0XXX1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 7 holders which blocks → TELNYX LLC 073H SALISBURY MD
2017-03-27 667-226 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - MD 876D STMICHAELS MD
2017-03-27 667-291 0XXX1XXX2XXX3XXX4XXX7XXX8XXX9XXX · 3 holders which blocks → ONVOY, LLC - MD 876D MILLINGTON MD
2017-03-24 667-220 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - MD 876D GREENSBORO MD
2017-03-24 667-285 0–9 XXXall 10 · 5 holders which blocks → ONVOY, LLC - MD 876D HURLOCK MD
2016-12-29 667-204 0–9 XXXall 10 · 5 holders which blocks → PAETEC ITEL, LLC 829J ANNAPOLIS MD
2016-12-02 667-402 0–9 XXXall 10 · 3 holders which blocks → TELNYX LLC 073H BALTIMORE MD
2016-11-22 667-240 0–9 XXXall 10 · 5 holders which blocks → BARR TELL USA, INC. 964H COLUMBIA MD
2016-11-22 667-967 0–9 XXXall 10 · 5 holders which blocks → BARR TELL USA, INC. 964H GLENBURNIE MD
2016-11-14 667-352 0–9 XXXall 10 · 3 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 ABERDEEN MD
2016-11-10 667-400 0–9 XXXall 10 · 4 holders which blocks → BARR TELL USA, INC. 964H BALTIMORE MD
2016-09-27 667-215 0–9 XXXall 10 · 7 holders which blocks → COMCAST IP PHONE, LLC 318J ELKTON MD
2016-08-23 667-808 0XXX1XXX7XXX8XXX9XXX · 5 holders which blocks → PEERLESS NETWORK OF MARYLAND, LLC 568G EASTON MD
2016-08-16 667-800 0–9 XXXall 10 · 2 holders which blocks → ONVOY, LLC - MD 876D SALISBURY MD
2016-06-21 667-321 0–9 XXXall 10 · 6 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 PRINCEFRCK MD
2016-05-25 667-281 0XXX1XXX2XXX3XXX4XXX6XXX7XXX9XXX · 4 holders which blocks → PEERLESS NETWORK OF MARYLAND, LLC 568G SALISBURY MD
2016-05-23 667-706 0–9 XXXall 10 · 5 holders which blocks → OMNIPOINT COMMUNICATIONS ENTERPRISES, LP 6626 ELKTON MD
2016-05-10 667-458 0–9 XXXall 10 · 8 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 ANNAPOLIS MD
2016-02-18 667-229 0–9 XXXall 10 · 5 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 ABERDEEN MD
2016-02-17 667-202 0–9 XXXall 10 · 2 holders which blocks → ONVOY, LLC - MD 876D ELKTON MD
2015-12-18 667-200 0–9 XXXall 10 · 5 holders which blocks → ONVOY, LLC - MD 876D COLUMBIA MD
2015-12-16 667-313 0–9 XXXwhole prefix which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 7228 PIKESVILLE MD
2015-12-04 667-771 0–9 XXXall 10 · 5 holders which blocks → WIDE VOICE, LLC - MD 530H BALTIMORE MD
2015-11-17 667-201 0–9 XXXall 10 · 6 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 BEL AIR MD
2015-11-04 667-786 0–9 XXXall 10 · 6 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 COLUMBIA MD
2015-10-19 667-701 0–9 XXXall 10 · 4 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 ELKRIDGE MD
2015-09-22 667-600 0–9 XXXall 10 · 6 holders which blocks → EVOLVE CELLULAR, INC. 139F BALTIMORE MD
2015-08-17 667-222 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - MD 876D ARGRGBSNIS 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.