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 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
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Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
— 817-748 2XXX9XXX · 2 holders which blocks → ONVOY, LLC - TX 903C GRAPEVINE TX
— 817-749 0XXX1XXX6XXX7XXX8XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 GRAPEVINE TX
— 817-750 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → BANDWIDTH.COM CLEC, LLC - TX 004F FORT WORTH TX
— 817-752 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → BANDWIDTH.COM CLEC, LLC - TX 004F AZLE TX
— 817-753 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 KELLER TX
— 817-754 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 RENO TX
— 817-755 0XXX1XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 SPRINGTOWN TX
— 817-756 0XXX1XXX3XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 GRAPEVINE TX
— 817-758 not yet reported which blocks → MATRIX TELECOM, LLC. S/I/I TNCI - TX 7715 CLEBURNE TX
— 817-759 9XXX which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-761 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → AT&T - LOCAL 7421 ALVARADO TX
— 817-762 0XXX which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-763 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-764 4XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 FORT WORTH TX
— 817-765 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - TX 903C KENNEDALE TX
— 817-766 0XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 NRICHLDHLS TX
— 817-767 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 ROANOKE TX
— 817-768 0XXX3XXX7XXX8XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 FORT WORTH TX
— 817-769 0XXX3XXX5XXX7XXX8XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 FORT WORTH TX
— 817-770 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - TX 7148 NRICHLDHLS TX
— 817-771 0XXX1XXX2XXX3XXX5XXX6XXX7XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TX 6506 WEATHERFD TX
— 817-774 0XXX1XXX2XXX3XXX4XXX9XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 CLEBURNE TX
— 817-775 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - TX 7148 KENNEDALE TX
— 817-777 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-778 0XXX1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 3 holders which blocks → FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 4344 GRAPEVINE TX
— 817-779 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 7 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - TX 7148 MANSFIELD TX
— 817-780 not yet reported which blocks → MATRIX TELECOM, LLC. S/I/I TNCI - TX 7715 GRANBURY TX
— 817-781 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 GLENDALE TX
— 817-782 8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-783 0XXX4XXX8XXX9XXX which blocks → SOUTHWESTERN BELL 9533 ALVARADO TX
— 817-784 5XXX7XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-785 3XXX4XXX7XXX8XXX9XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 EULESS TX
— 817-786 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 EULESS TX
— 817-787 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-788 not yet reported which blocks → SOUTHWESTERN BELL 9533 NRICHLDHLS TX
— 817-790 1XXX4XXX9XXX which blocks → SOUTHWESTERN BELL 9533 ALVARADO TX
— 817-791 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-792 not yet reported which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-793 not yet reported which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-794 not yet reported which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-795 not yet reported which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-797 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-798 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-799 1XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - TX 7148 EULESS TX
— 817-800 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-801 not yet reported which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-803 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → ONVOY, LLC - TX 903C EULESS TX
— 817-804 not yet reported which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-805 4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 ARLINGTON TX
— 817-806 4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - TX 7148 FORT WORTH TX

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.