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 501
SOUTHWESTERN BELL 165
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
— 501-653 3XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 BRYANTCGVL AR
— 501-660 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-661 5XXX which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-663 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-664 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-666 none assigned yet which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-669 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 CLEVELAND AR
— 501-671 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-676 8XXX which blocks → SOUTHWESTERN BELL 9533 LONOKE AR
— 501-683 8XXX9XXX which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-686 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-688 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-701 0XXX2XXX3XXX4XXX7XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 HOTSPRINGS AR
— 501-716 7XXX8XXX which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-721 not yet reported which blocks → SOUTHWESTERN BELL 9533 XXXXXXXXXX AR
— 501-727 2XXX3XXX4XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 MORRILTON AR
— 501-730 not yet reported which blocks → SOUTHWESTERN BELL 9533 CONWAY AR
— 501-753 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-758 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-760 0XXX5XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 HOTSPRINGS AR
— 501-764 0XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → SOUTHWESTERN BELL 9533 CONWAY AR
— 501-767 not yet reported which blocks → SOUTHWESTERN BELL 9533 HOTSPRINGS AR
— 501-771 3XXX which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-776 not yet reported which blocks → SOUTHWESTERN BELL 9533 BENTON AR
— 501-778 not yet reported which blocks → SOUTHWESTERN BELL 9533 BENTON AR
— 501-791 1XXX4XXX6XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-794 3XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 BENTON AR
— 501-803 2XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 PALARM AR
— 501-812 3XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-813 0XXX2XXX4XXX5XXX6XXX7XXX9XXX which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-815 5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 JONESMILLS AR
— 501-819 0XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 SYVNHLSHWD AR
— 501-821 not yet reported which blocks → SOUTHWESTERN BELL 9533 FERNDALE AR
— 501-825 0XXX2XXX3XXX4XXX5XXX9XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 GREERSFRRY AR
— 501-833 4XXX5XXX6XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 SYVNHLSHWD AR
— 501-834 not yet reported which blocks → SOUTHWESTERN BELL 9533 SYVNHLSHWD AR
— 501-835 not yet reported which blocks → SOUTHWESTERN BELL 9533 SYVNHLSHWD AR
— 501-840 0XXX which blocks → SOUTHWESTERN BELL 9533 BENTON AR
— 501-844 8XXX which blocks → SOUTHWESTERN BELL 9533 JONESMILLS AR
— 501-847 not yet reported which blocks → SOUTHWESTERN BELL 9533 BRYANTCGVL AR
— 501-851 9XXX which blocks → SOUTHWESTERN BELL 9533 PALARM AR
— 501-860 5XXX8XXX9XXX which blocks → SOUTHWESTERN BELL 9533 BENTON AR
— 501-862 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-868 3XXX which blocks → SOUTHWESTERN BELL 9533 PINNACLE AR
— 501-882 not yet reported which blocks → SOUTHWESTERN BELL 9533 BEEBE AR
— 501-887 1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → SOUTHWESTERN BELL 9533 HEBER SPG AR
— 501-888 9XXX which blocks → SOUTHWESTERN BELL 9533 SPRINGLAKE AR
— 501-893 0XXX3XXX4XXX5XXX7XXX8XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 CENTER RDG AR
— 501-897 3XXX6XXX7XXX8XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 WRIGHTSVL AR
— 501-915 1XXX4XXX5XXX6XXX7XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 JESSIEVL AR

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.