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
— 817-625 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-626 not yet reported which blocks → SOUTHWESTERN BELL 9533 FORT WORTH TX
— 817-627 4XXX5XXX7XXX8XXX9XXX which blocks → GRANDE COMMUNICATIONS NETWORKS, INC. - TX 7670 ARLINGTON TX
— 817-628 0XXX7XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 ATLAS TX
— 817-629 0XXX2XXX4XXX5XXX7XXX8XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 WEATHERFD TX
— 817-631 0–9 XXXall 10 · 3 holders which blocks → ONVOY, LLC - TX 903C RENO TX
— 817-632 not yet reported which blocks → ONVOY, LLC - TX 903C FORT WORTH TX
— 817-633 not yet reported which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-634 0XXX2XXX5XXX7XXX8XXX9XXX · 2 holders which blocks → U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 671J KENNEDALE TX
— 817-635 0XXX2XXX4XXX5XXX9XXX · 3 holders which blocks → ONVOY, LLC - TX 903C ARLINGTON TX
— 817-636 not yet reported which blocks → BRIGHTSPEED OF TEXAS, INC. 2114 RHOME TX
— 817-637 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-638 not yet reported which blocks → BRIGHTSPEED OF TEXAS, INC. 2114 RHOME TX
— 817-639 not yet reported which blocks → LEVEL 3 OF TELECOM OF TEXAS, LLC - TX 7516 FORT WORTH TX
— 817-640 not yet reported which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-641 not yet reported which blocks → SOUTHWESTERN BELL 9533 CLEBURNE TX
— 817-642 5XXX7XXX8XXX9XXX · 3 holders which blocks → GRANDE COMMUNICATIONS NETWORKS, INC. - TX 7670 ARLINGTON TX
— 817-643 not yet reported which blocks → GRANDE COMMUNICATIONS NETWORKS, INC. - TX 7670 EULESS TX
— 817-644 not yet reported which blocks → GRANDE COMMUNICATIONS NETWORKS, INC. - TX 7670 FORT WORTH TX
— 817-645 not yet reported which blocks → SOUTHWESTERN BELL 9533 CLEBURNE TX
— 817-646 0–9 XXXwhole prefix which blocks → ONVOY, LLC - TX 903C ATLAS TX
— 817-647 0–9 XXXwhole prefix which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 GLENDALE TX
— 817-648 0XXX8XXX9XXX which blocks → SOUTHWESTERN BELL 9533 CLEBURNE TX
— 817-649 9XXX which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-650 0–9 XXXall 10 · 3 holders which blocks → T-MOBILE USA, INC. 6529 GRANBURY TX
— 817-651 not yet reported which blocks → SPOK, INC. 6630 ARLINGTON TX
— 817-652 not yet reported which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-654 not yet reported which blocks → SOUTHWESTERN BELL 9533 GLENDALE TX
— 817-656 not yet reported which blocks → SOUTHWESTERN BELL 9533 NRICHLDHLS TX
— 817-657 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-658 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-662 0XXX2XXX4XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 EULESS TX
— 817-663 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - TX 903C NRICHLDHLS TX
— 817-664 0XXX3XXX7XXX8XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 ARLINGTON TX
— 817-665 not yet reported which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 FORT WORTH TX
— 817-667 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 ARLINGTON TX
— 817-668 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 SPRINGTOWN TX
— 817-669 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 ARLINGTON TX
— 817-671 not yet reported which blocks → SPOK, INC. 6630 ARLINGTON TX
— 817-672 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - TX 903C KENNEDALE TX
— 817-673 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-674 5XXX7XXX8XXX9XXX · 3 holders which blocks → ONVOY, LLC - TX 903C ROANOKE TX
— 817-676 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-677 0XXX1XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 2154 RENO TX
— 817-679 1XXX which blocks → SOUTHWESTERN BELL 9533 ARLINGTON TX
— 817-680 none assigned yet which blocks → METROPCS, INC. 5562 ARLINGTON TX
— 817-683 none assigned yet which blocks → T-MOBILE USA, INC. 6529 ARLINGTON TX
— 817-684 not yet reported which blocks → SOUTHWESTERN BELL 9533 EULESS TX
— 817-685 not yet reported which blocks → SOUTHWESTERN BELL 9533 EULESS TX
— 817-686 none assigned yet which blocks → ONVOY, LLC - TX 903C ATLAS 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.