NumberResearch Membership · Data 09/19/2026

Recent prefix assignments

5 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 951
ONVOY, LLC - CA 5
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
2021-07-29 951-586 0–9 XXXwhole prefix which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RIVERSIDE CA
2021-07-29 951-589 0–9 XXXall 10 · 4 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RIVERSIDE CA
2021-07-29 951-590 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 HEMT HEMT CA
2021-07-13 951-944 0–9 XXXall 10 · 4 holders which blocks → FRACTEL, LLC 965H ARLINGTON CA
2021-04-29 951-583 0–9 XXXall 10 · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 ELSINORE CA
2021-04-29 951-584 0–9 XXXall 10 · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RIVERSIDE CA
2021-04-23 951-910 0XXX1XXX2XXX3XXX4XXX5XXX7XXX9XXX · 4 holders which blocks → ONVOY, LLC - CA 649C HEMT SAGE CA
2021-04-12 951-629 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 HEMT SNJC CA
2021-04-05 951-576 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 WOODCREST CA
2021-04-05 951-580 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 PERRIS CA
2021-02-25 951-866 0–9 XXXall 10 · 3 holders which blocks → FRACTEL, LLC 965H RIVERSIDE CA
2021-02-19 951-578 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 ARLINGTON CA
2021-02-01 951-574 0–9 XXXall 10 · 4 holders which blocks → TELNYX LLC 073H MURRIETA CA
2021-01-18 951-569 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 MORENO CA
2020-12-16 951-564 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 PERRIS CA
2020-12-16 951-568 0–9 XXXwhole prefix which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RIVERSIDE CA
2020-12-16 951-573 0–9 XXXall 10 · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RIVERSIDE CA
2020-12-09 951-560 0–9 XXXwhole prefix which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RIVERSIDE CA
2020-11-06 951-899 0–9 XXXall 10 · 3 holders which blocks → FRACTEL, LLC 965H RIVERSIDE CA
2020-10-28 951-558 0–9 XXXwhole prefix which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RIVERSIDE CA
2020-09-28 951-557 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 TEMSCL CNY CA
2020-09-21 951-724 0XXX1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 4 holders which blocks → FRACTEL, LLC 965H HEMT HMLD CA
2020-09-17 951-844 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → FRACTEL, LLC 965H IDYLLWILD CA
2020-09-08 951-554 0–9 XXXall 10 · 4 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RIVERSIDE CA
2020-09-01 951-548 0–9 XXXall 10 · 2 holders which blocks → T-MOBILE USA, INC. 6529 RIVERSIDE CA
2020-08-21 951-546 0–9 XXXall 10 · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 TEMSCL CNY CA
2020-08-05 951-542 0–9 XXXall 10 · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RIVERSIDE CA
2020-07-02 951-577 0–9 XXXall 10 · 4 holders which blocks → FRACTEL, LLC 965H CORONA CA
2020-07-02 951-633 0–9 XXXall 10 · 4 holders which blocks → FRACTEL, LLC 965H HEMT HEMT CA
2020-07-02 951-644 0–9 XXXall 10 · 4 holders which blocks → FRACTEL, LLC 965H BANNING CA
2020-07-02 951-946 0–9 XXXall 10 · 4 holders which blocks → FRACTEL, LLC 965H HEMT SNJC CA
2020-06-11 951-535 0–9 XXXall 10 · 6 holders which blocks → VONAGE AMERICA LLC 197D MURRIETA CA
2020-06-02 951-528 0–9 XXXall 10 · 3 holders which blocks → VONAGE AMERICA LLC 197D TEMECULA CA
2020-03-18 951-521 0–9 XXXall 10 · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RIVERSIDE CA
2020-02-28 951-519 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 TEMSCL CNY CA
2020-01-17 951-517 0–9 XXXall 10 · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 TEMECULA CA
2020-01-10 951-480 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 HEMT HEMT CA
2019-11-27 951-516 0–9 XXXall 10 · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 SUN CITY CA
2019-11-15 951-513 0–9 XXXall 10 · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 HEMT HMLD CA
2019-11-15 951-539 0–9 XXXall 10 · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 ARLINGTON CA
2019-11-11 951-508 0–9 XXXall 10 · 7 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CA 7240 CORONA CA
2019-10-02 951-507 0–9 XXXall 10 · 5 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 MIRA LOMA CA
2019-05-20 951-499 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - CA 649C BANNING CA
2019-05-13 951-855 0–9 XXXall 10 · 3 holders which blocks → FRACTEL, LLC 965H TEMSCL CNY CA
2019-05-13 951-877 0–9 XXXall 10 · 3 holders which blocks → FRACTEL, LLC 965H RIVERSIDE CA
2019-05-13 951-933 0–9 XXXall 10 · 6 holders which blocks → FRACTEL, LLC 965H PERRIS CA
2019-05-13 951-988 0–9 XXXall 10 · 7 holders which blocks → FRACTEL, LLC 965H MORENO CA
2019-04-23 951-799 0–9 XXXall 10 · 6 holders which blocks → HD CARRIER LLC 321J HEMT ANZA CA
2019-03-28 951-503 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 PERRIS CA
2019-03-15 951-498 0–9 XXXall 10 · 3 holders which blocks → METROPCS NETWORKS, LLC 899D ELSINORE CA

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.