NumberResearch Membership · Data 09/20/2026

Recent prefix assignments

2 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, last 30 days — NPA 475
ONVOY, LLC - CT 2
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
2014-11-25 475-434 0–9 XXXall 10 · 4 holders which blocks → METROPCS, INC. 5562 NEW HAVEN CT
2014-10-07 475-777 0–9 XXXall 10 · 8 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F ANSONIDRBY CT
2014-10-07 475-888 0–9 XXXall 10 · 6 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F FAIRFIELD CT
2014-10-03 475-288 0–9 XXXall 10 · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CT 4800 NORWALK CT
2014-08-15 475-221 0–9 XXXall 10 · 4 holders which blocks → BANDWIDTH.COM CLEC, LLC - CT 199F BRANFORD CT
2014-07-22 475-246 0–9 XXXwhole prefix which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEW HAVEN CT
2014-07-22 475-247 0–9 XXXwhole prefix which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEW HAVEN CT
2014-07-22 475-248 0–9 XXXwhole prefix which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 BRIDGEPORT CT
2014-07-22 475-249 0–9 XXXwhole prefix which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 OLDGRNWICH CT
2014-07-21 475-209 0–9 XXXall 10 · 6 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEW HAVEN CT
2014-06-26 475-215 0–9 XXXall 10 · 6 holders which blocks → CENTURYLINK COMMUNICATIONS, LLC 508J RIDGEFIELD CT
2014-06-16 475-277 0–9 XXXall 10 · 8 holders which blocks → CENTURYLINK COMMUNICATIONS, LLC 508J WILTON CT
2014-05-23 475-223 0–9 XXXall 10 · 6 holders which blocks → OMNIPOINT COMMUNICATIONS, INC. - CT 6624 ANSONIDRBY CT
2014-05-22 475-289 0–9 XXXall 10 · 7 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 DANBURY CT
2014-05-22 475-355 0–9 XXXall 10 · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 NEW HAVEN CT
2014-04-30 475-328 0–9 XXXall 10 · 8 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT 7230 DARIEN CT
2014-03-25 475-329 0–9 XXXall 10 · 4 holders which blocks → BANDWIDTH.COM CLEC, LLC - CT 199F DANBURY CT
2013-02-08 475-243 0–9 XXXall 10 · 5 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F ANSONIDRBY CT
2013-02-08 475-444 0–9 XXXall 10 · 7 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F NEWTOWN CT
2013-02-08 475-999 0–9 XXXall 10 · 7 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F FAIRFIELD CT
2013-01-30 475-675 0–9 XXXall 10 · 6 holders which blocks → BANDWIDTH.COM CLEC, LLC - CT 199F SEYMOUR CT
2012-12-20 475-204 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 DANBURY CT
2012-12-20 475-422 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 BRIDGEPORT CT
2012-11-20 475-222 0–9 XXXall 10 · 4 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F WATERBURY CT
2012-11-13 475-212 0–9 XXXall 10 · 6 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F NAUGATUCK CT
2012-10-02 475-239 0–9 XXXall 10 · 6 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F TRUMBULL CT
2012-08-23 475-205 0–9 XXXall 10 · 2 holders which blocks → CENTURYLINK COMMUNICATIONS, LLC 508J STAMFORD CT
2012-06-29 475-200 0–9 XXXall 10 · 2 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F HUNTINGTON CT
2011-09-16 475-298 0–9 XXXall 10 · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 BRIDGEPORT CT
2011-09-16 475-529 0–9 XXXall 10 · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 DANBURY CT
2011-08-29 475-282 0–9 XXXall 10 · 5 holders which blocks → BANDWIDTH.COM CLEC, LLC - CT 199F BRIDGEPORT CT
2011-07-05 475-235 0–9 XXXall 10 · 6 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 WATERBURY CT
2011-06-13 475-227 0–9 XXXall 10 · 4 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 NEW HAVEN CT
2011-04-19 475-202 0–9 XXXall 10 · 5 holders which blocks → OMNIPOINT COMMUNICATIONS, INC. - CT 6624 NEW HAVEN CT
2010-05-21 475-238 0–9 XXXall 10 · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 NEW HAVEN CT
2010-02-17 475-201 0–9 XXXall 10 · 5 holders which blocks → METROPCS, INC. 5562 NEW HAVEN CT
2009-08-07 475-882 0–9 XXXall 10 · 5 holders which blocks → PAETEC ITEL, LLC 829J HUNTINGTON CT
— 475-211 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CT
— 475-264 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - CT 639C DARIEN CT
— 475-311 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CT
— 475-411 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CT
— 475-449 0–9 XXXall 10 · 4 holders which blocks → OMNIPOINT COMMUNICATIONS, INC. - CT 6624 BRIDGEPORT CT
— 475-465 0–9 XXXall 10 · 5 holders which blocks → ONVOY, LLC - CT 639C OLDGRNWICH CT
— 475-511 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CT
— 475-555 not yet reported which blocks → MULTIPLE OCN LISTING MULT DIR ASST CT
— 475-611 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CT
— 475-700 not yet reported which blocks → CT
— 475-711 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CT
— 475-811 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CT
— 475-911 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CT

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.