NumberResearch Membership · Data 09/19/2026

Recent prefix assignments

0 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, all time — NPA 817
SOUTHWESTERN BELL 302
NEW CINGULAR WIRELESS PCS, LLC - IL 88
T-MOBILE USA, INC. 54
LEVEL 3 COMMUNICATIONS, LLC - TX 45
ONVOY, LLC - TX 43
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
Clear Download CSV ↓
Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
— 817-687 6XXX7XXX8XXX9XXX · 2 holders which blocks → ONVOY, LLC - TX 903C GLENDALE TX
— 817-688 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 GLENDALE TX
— 817-689 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-690 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-691 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-692 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 GLENDALE TX
— 817-695 5XXX which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-696 0XXX1XXX3XXX5XXX6XXX7XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-698 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-700 not yet reported which blocks → TX
— 817-701 4XXX5XXX6XXX8XXX9XXX · 2 holders which blocks → ONVOY, LLC - TX 903C ARLINGTON TX
— 817-703 not yet reported which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-704 5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 ARLINGTON TX
— 817-705 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-706 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-707 none assigned yet which blocks → METROPCS, INC. 5562 ARLINGTON TX
— 817-708 2XXX which blocks → LEVEL 3 OF TELECOM OF TEXAS, LLC - TX 7516 FORT WORTH TX
— 817-709 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 GLENDALE TX
— 817-711 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX TX
— 817-712 not yet reported which blocks → LEVEL 3 OF TELECOM OF TEXAS, LLC - TX 7516 NRICHLDHLS TX
— 817-713 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 GLENDALE TX
— 817-714 not yet reported which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-715 not yet reported which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-717 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 FORT WORTH TX
— 817-719 5XXX6XXX7XXX8XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 ARLINGTON TX
— 817-720 0XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 FORT WORTH TX
— 817-721 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-722 4XXX5XXX6XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - TX 7148 GRAPEVINE TX
— 817-723 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-724 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 4344 GRAPEVINE TX
— 817-725 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 RENO TX
— 817-726 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-728 9XXX which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J MANSFIELD TX
— 817-729 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-730 1XXX3XXX4XXX5XXX6XXX8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-731 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-732 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-734 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → GRANDE COMMUNICATIONS NETWORKS, INC. - TX 7670 GLENDALE TX
— 817-735 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-736 2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 GRANBURY TX
— 817-737 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-738 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-740 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-741 not yet reported which blocks → MILLENNIUM TELCOM, LLC DBA ONESOURCE COMM. - TX 4009 KELLER TX
— 817-742 0XXX2XXX which blocks → BANDWIDTH.COM CLEC, LLC - TX 004F ROANOKE TX
— 817-743 0XXX1XXX2XXX3XXX5XXX6XXX9XXX which blocks → T-MOBILE USA, INC. 6529 NRICHLDHLS TX
— 817-744 0XXX7XXX8XXX9XXX · 3 holders which blocks → CHARTER IP ENABLED SERVICES, LLC 792K FORT WORTH TX
— 817-745 0XXX5XXX6XXX7XXX9XXX which blocks → ONVOY, LLC - TX 903C KELLER TX
— 817-746 none assigned yet which blocks → BANDWIDTH.COM CLEC, LLC - TX 004F ROANOKE TX
— 817-747 0XXX1XXX2XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → ONVOY SPECTRUM, LLC 624H NRICHLDHLS TX

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.