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 661
ONVOY, LLC - CA 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
2023-04-12 661-605 0–9 XXXall 10 · 2 holders which blocks → COMCAST PHONE OF CALIFORNIA, LLC 394L BKFD MAIN CA
2023-04-12 661-608 6XXX7XXX which blocks → ONVOY SPECTRUM, LLC 624H HI VISTA CA
2023-04-12 661-730 6XXX7XXX which blocks → ONVOY SPECTRUM, LLC 624H PLDL AGDL CA
2023-03-10 661-701 0–9 XXXwhole prefix which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 PLDL PLDL CA
2023-02-17 661-604 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 LANCASTER CA
2023-02-10 661-603 0–9 XXXall 10 · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 PLDL PLDL CA
2022-11-23 661-651 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - CA 649C SNCA NHCS CA
2022-10-21 661-598 0–9 XXXall 10 · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 PLDL PLDL CA
2022-10-11 661-602 0–9 XXXall 10 · 3 holders which blocks → BANDWIDTH.COM CLEC, LLC - CA 981E BKFD SOUTH CA
2022-10-10 661-597 0XXX1XXX2XXX7XXX9XXX · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 MOJAVE CA
2022-09-02 661-594 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 SHAFTER CA
2022-07-20 661-610 0–9 XXXall 10 · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7139 BKFD MAIN CA
2022-07-13 661-649 0–9 XXXall 10 · 3 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J ARVIN CA
2022-06-29 661-590 0XXX1XXX2XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J WASCO CA
2022-05-26 661-595 0–9 XXXall 10 · 4 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J BKFD MAIN CA
2022-05-26 661-687 0–9 XXXall 10 · 5 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J BKFD SOUTH CA
2022-04-25 661-653 0–9 XXXall 10 · 6 holders which blocks → T-MOBILE USA, INC. 6529 DELANO CA
2022-04-12 661-571 0–9 XXXall 10 · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 LANCASTER CA
2022-03-09 661-570 0–9 XXXall 10 · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 6006 BKFD SOUTH CA
2022-02-24 661-601 0–9 XXXall 10 · 4 holders which blocks → COMMIO, LLC 939H BKFD NORTH CA
2022-02-18 661-639 7XXX8XXX · 2 holders which blocks → TON80 COMMUNICATIONS, LLC 516J LAKEHUGHES CA
2021-12-10 661-569 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 BKFD MAIN CA
2021-12-08 661-625 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 SNCA NHCS CA
2021-11-15 661-936 0–9 XXXwhole prefix which blocks → T-MOBILE USA, INC. 6529 PLDL PLDL CA
2021-11-12 661-539 0–9 XXXall 10 · 3 holders which blocks → ONVOY SPECTRUM, LLC 624H MCFARLAND CA
2021-11-12 661-581 0–9 XXXall 10 · 5 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CA 7139 PLDL PLDL CA
2021-10-28 661-531 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 ARVIN CA
2021-09-22 661-550 0XXX1XXX2XXX7XXX8XXX9XXX · 3 holders which blocks → BANDWIDTH.COM CLEC, LLC - CA 981E BIG BUTTE CA
2021-09-02 661-580 0–9 XXXall 10 · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 PLDL PLDL CA
2021-07-29 661-521 0–9 XXXall 10 · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 PLDL PLDL CA
2021-07-13 661-933 0–9 XXXall 10 · 4 holders which blocks → FRACTEL, LLC 965H BKFD NORTH CA
2021-06-30 661-519 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 ARVIN CA
2021-06-07 661-887 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - CA 649C PLDL PLDL CA
2021-04-29 661-508 0–9 XXXwhole prefix which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 PLDL PLDL CA
2021-04-08 661-934 0–9 XXXall 10 · 3 holders which blocks → TON80 COMMUNICATIONS, LLC 516J ARVIN CA
2021-02-16 661-627 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 SNCA NHCS CA
2021-02-03 661-660 0–9 XXXall 10 · 2 holders which blocks → ONVOY SPECTRUM, LLC 624H SNCA SGCC CA
2021-02-02 661-518 0–9 XXXall 10 · 6 holders which blocks → TELNYX LLC 073H TEHACHAPI CA
2021-01-21 661-922 0XXX1XXX2XXX3XXX7XXX8XXX9XXX · 5 holders which blocks → FRACTEL, LLC 965H DELANO CA
2020-11-25 661-624 0–9 XXXall 10 · 5 holders which blocks → IP HORIZON LLC 515J BKFD SOUTH CA
2020-11-09 661-955 0–9 XXXall 10 · 4 holders which blocks → FRACTEL, LLC 965H ARVIN CA
2020-10-16 661-545 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 DELANO CA
2020-10-05 661-509 0–9 XXXall 10 · 2 holders which blocks → BANDWIDTH.COM CLEC, LLC - CA 981E BKFD SOUTH CA
2020-09-30 661-516 0–9 XXXall 10 · 4 holders which blocks → HD CARRIER LLC 321J BKFD MAIN CA
2020-09-23 661-512 0–9 XXXall 10 · 5 holders which blocks → METROPCS NETWORKS, LLC 899D PLDL AGDL CA
2020-09-21 661-744 0–9 XXXall 10 · 4 holders which blocks → FRACTEL, LLC 965H PLDL PLDL CA
2020-09-21 661-866 0–9 XXXall 10 · 3 holders which blocks → FRACTEL, LLC 965H BKFD MAIN CA
2020-09-17 661-514 0–9 XXXall 10 · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 MCFARLAND CA
2020-09-08 661-506 0–9 XXXall 10 · 5 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 PLDL PLDL CA
2020-08-04 661-504 0–9 XXXall 10 · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 PLDL PLDL 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.