NumberResearch Membership · Data 09/20/2026

Recent prefix assignments

0 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, all time — NPA 628
FRACTEL, LLC 33
ONVOY, LLC - CA 32
T-MOBILE USA, INC. 28
TELEPORT COMMUNICATIONS AMERICA, LLC - CA 17
BANDWIDTH.COM CLEC, LLC - CA 13
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
2016-04-01 628-202 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 BELVEDERE CA
2016-03-04 628-237 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 SAUSALITO CA
2016-02-29 628-899 0–9 XXXall 10 · 5 holders which blocks → PEERLESS NETWORK OF CALIFORNIA, LLC - CA 373F SNFC MT-EV CA
2016-02-18 628-228 0–9 XXXall 10 · 6 holders which blocks → PACIFIC BELL 9740 SNFC CNTRL CA
2016-02-15 628-877 0–9 XXXall 10 · 2 holders which blocks → ONVOY, LLC - CA 649C CORTEMADRA CA
2016-02-12 628-220 0–9 XXXall 10 · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CA 8826 SNFC CNTRL CA
2016-02-04 628-236 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 NOVATO CA
2015-12-01 628-201 0–9 XXXall 10 · 5 holders which blocks → ONVOY, LLC - CA 649C SNFC CNTRL CA
2015-12-01 628-235 0–9 XXXall 10 · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CA 8826 SNFC CNTRL CA
2015-12-01 628-243 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - CA 649C SAN RAFAEL CA
2015-11-13 628-226 0–9 XXXall 10 · 5 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 BELVEDERE CA
2015-10-27 628-231 0–9 XXXall 10 · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7145 SNFC CNTRL CA
2015-10-05 628-233 0–9 XXXall 10 · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 SNFC CNTRL CA
2015-10-02 628-224 0–9 XXXall 10 · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 SNFC MT-EV CA
2015-10-02 628-225 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 SNFC CNTRL CA
2015-09-16 628-223 0–9 XXXall 10 · 2 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7145 SNFC CNTRL CA
2015-07-14 628-221 0–9 XXXall 10 · 5 holders which blocks → CENTURYLINK COMMUNICATIONS, LLC 508J SNFC CNTRL CA
2015-06-02 628-206 0–9 XXXwhole prefix which blocks → PACIFIC BELL 9740 SNFC CNTRL CA
2015-04-10 628-242 0–9 XXXall 10 · 4 holders which blocks → PACIFIC BELL 9740 SNFC CNTRL CA
2015-03-26 628-500 0–9 XXXwhole prefix which blocks → ONVOY, LLC - CA 649C SAN RAFAEL CA
2015-03-17 628-300 0–9 XXXall 10 · 2 holders which blocks → ONVOY, LLC - CA 649C SNFC CNTRL CA
2015-03-13 628-234 0–9 XXXall 10 · 8 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J SAN RAFAEL CA
2014-10-07 628-232 0–9 XXXall 10 · 4 holders which blocks → PEERLESS NETWORK OF CALIFORNIA, LLC - CA 373F INVERNESS CA
2014-10-01 628-400 0–9 XXXall 10 · 2 holders which blocks → ONVOY, LLC - CA 649C SNFC CNTRL CA
2014-10-01 628-600 0–9 XXXall 10 · 2 holders which blocks → ONVOY, LLC - CA 649C SNFC CNTRL CA
2014-10-01 628-800 0–9 XXXall 10 · 2 holders which blocks → ONVOY, LLC - CA 649C SNFC CNTRL CA
2014-09-30 628-444 0–9 XXXall 10 · 6 holders which blocks → ONVOY, LLC - CA 649C SNFC CNTRL CA
2014-09-29 628-222 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - CA 649C SNFC CNTRL CA
— 628-200 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - CA 649C SNFC JUNPR CA
— 628-211 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 628-227 0–9 XXXall 10 · 4 holders which blocks → BANDWIDTH.COM CLEC, LLC - CA 981E SNFC MT-EV CA
— 628-238 0–9 XXXall 10 · 6 holders which blocks → PEERLESS NETWORK OF CALIFORNIA, LLC - CA 373F IGNACIO CA
— 628-261 0–9 XXXall 10 · 4 holders which blocks → TERRA NOVA TELECOM INC. 145J SAUSALITO CA
— 628-271 0–9 XXXall 10 · 3 holders which blocks → ONVOY SPECTRUM, LLC 624H SNFC CNTRL CA
— 628-282 0–9 XXXall 10 · 5 holders which blocks → AT&T - LOCAL 7421 SNFC JUNPR CA
— 628-311 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 628-333 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - CA 649C SNFC CNTRL CA
— 628-358 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 SNFC CNTRL CA
— 628-411 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 628-415 not yet reported which blocks → CA
— 628-466 0–9 XXXall 10 · 5 holders which blocks → ONVOY, LLC - CA 649C SNFC CNTRL CA
— 628-511 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 628-555 not yet reported which blocks → MULTIPLE OCN LISTING MULT DIR ASST CA
— 628-611 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 628-666 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - CA 649C IGNACIO CA
— 628-700 not yet reported which blocks → CA
— 628-711 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 628-777 0–9 XXXall 10 · 5 holders which blocks → ONVOY, LLC - CA 649C SNFC MT-EV CA
— 628-789 0–9 XXXall 10 · 5 holders which blocks → LEAP TELECOM, LLC 616J SNFC CNTRL CA
— 628-811 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA

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.