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
2020-02-05 475-265 0–9 XXXall 10 · 4 holders which blocks → BANDWIDTH.COM CLEC, LLC - CT 199F TRUMBULL CT
2019-12-17 475-477 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - CT 639C STAMFORD CT
2019-10-25 475-261 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 NEW HAVEN CT
2019-10-01 475-263 0–9 XXXall 10 · 7 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F WATERBURY CT
2019-09-12 475-258 0–9 XXXall 10 · 4 holders which blocks → OMNIPOINT COMMUNICATIONS, INC. - CT 6624 NORWALK CT
2019-07-15 475-471 0–9 XXXwhole prefix which blocks → ONVOY, LLC - CT 639C WESTPORT CT
2019-07-15 475-472 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - CT 639C WILTON CT
2019-07-15 475-473 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - CT 639C WOODBURY CT
2019-07-15 475-500 0–9 XXXall 10 · 2 holders which blocks → ONVOY, LLC - CT 639C GREENWICH CT
2019-07-15 475-600 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → ONVOY, LLC - CT 639C SEYMOUR CT
2019-07-15 475-900 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - CT 639C GUILFORD CT
2019-05-23 475-262 0–9 XXXall 10 · 5 holders which blocks → BANDWIDTH.COM CLEC, LLC - CT 199F HUNTINGTON CT
2019-03-28 475-257 0–9 XXXall 10 · 4 holders which blocks → CSC WIRELESS, LLC 425J NORWALK CT
2019-03-26 475-476 0–9 XXXall 10 · 6 holders which blocks → ONVOY, LLC - CT 639C BRIDGEPORT CT
2019-03-05 475-739 0–9 XXXall 10 · 6 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F WOLCOTT CT
2018-12-24 475-216 0–9 XXXall 10 · 5 holders which blocks → OMNIPOINT COMMUNICATIONS, INC. - CT 6624 ANSONIDRBY CT
2018-12-24 475-256 0–9 XXXall 10 · 4 holders which blocks → OMNIPOINT COMMUNICATIONS, INC. - CT 6624 DANBURY CT
2018-11-27 475-557 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 WATERBURY CT
2018-10-24 475-253 0–9 XXXall 10 · 6 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F WALLINGFD CT
2018-10-24 475-254 0–9 XXXall 10 · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 NEW HAVEN CT
2018-10-05 475-255 0–9 XXXall 10 · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 MERIDEN CT
2018-09-21 475-701 0–9 XXXall 10 · 5 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F NAUGATUCK CT
2018-09-20 475-252 0–9 XXXall 10 · 4 holders which blocks → CABLEVISION LIGHTPATH, INC. - CT 4950 BYRAM CT
2018-09-05 475-251 0–9 XXXall 10 · 4 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 ANSONIDRBY CT
2018-08-28 475-685 0–9 XXXall 10 · 6 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 STAMFORD CT
2018-07-23 475-250 0–9 XXXall 10 · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 NORWALK CT
2018-07-11 475-241 0–9 XXXall 10 · 6 holders which blocks → METROPCS, INC. 5562 NEW HAVEN CT
2018-04-20 475-459 0–9 XXXall 10 · 2 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 NORWALK CT
2018-02-21 475-244 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - CT 639C CHESHIRE CT
2018-02-09 475-889 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 NORWALK CT
2017-12-27 475-237 0–9 XXXall 10 · 6 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 DANBURY CT
2017-11-21 475-400 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - CT 639C STAMFORD CT
2017-09-28 475-800 0–9 XXXall 10 · 2 holders which blocks → ONVOY, LLC - CT 639C NEW HAVEN CT
2017-09-25 475-259 0–9 XXXall 10 · 4 holders which blocks → METROPCS, INC. 5562 DARIEN CT
2017-09-21 475-338 0–9 XXXall 10 · 4 holders which blocks → COMCAST IP PHONE, LLC 318J BRANFORD CT
2017-09-01 475-236 0–9 XXXall 10 · 6 holders which blocks → OMNIPOINT COMMUNICATIONS, INC. - CT 6624 BRIDGEPORT CT
2017-07-12 475-393 0–9 XXXall 10 · 4 holders which blocks → OMNIPOINT COMMUNICATIONS, INC. - CT 6624 NORWALK CT
2017-06-29 475-242 0–9 XXXall 10 · 4 holders which blocks → PEERLESS NETWORK OF CONNECTICUT, LLC - CT 539F REDDING CT
2017-04-14 475-359 0–9 XXXall 10 · 6 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 STAMFORD CT
2017-02-27 475-333 0–9 XXXall 10 · 4 holders which blocks → TELNYX LLC 073H STAMFORD CT
2016-12-05 475-234 0–9 XXXall 10 · 6 holders which blocks → TELNYX LLC 073H NEW HAVEN CT
2016-11-08 475-233 0–9 XXXall 10 · 8 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 WATERBURY CT
2016-09-29 475-319 0–9 XXXall 10 · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 BRIDGEPORT CT
2016-08-01 475-231 0–9 XXXall 10 · 7 holders which blocks → CHARTER IP ENABLED SERVICES, LLC 792K TRUMBULL CT
2016-07-25 475-232 0–9 XXXall 10 · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CT 4800 STAMFORD CT
2016-07-01 475-217 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 STAMFORD CT
2016-07-01 475-229 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 STAMFORD CT
2016-06-03 475-300 0–9 XXXall 10 · 4 holders which blocks → VONAGE AMERICA LLC 197D NEW HAVEN CT
2016-04-25 475-214 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 STAMFORD CT
2016-04-25 475-322 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 NORWALK 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.