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 870
SOUTHWESTERN BELL 154
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
— 870-737 0XXX5XXX7XXX8XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 PORTLAND AR
— 870-739 0XXX6XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 MARION AR
— 870-744 0XXX1XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → SOUTHWESTERN BELL 9533 TUPELO AR
— 870-748 0XXX4XXX5XXX7XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 CALION AR
— 870-753 2XXX3XXX4XXX5XXX6XXX8XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 HELENA AR
— 870-755 0XXX3XXX4XXX6XXX8XXX9XXX · 6 holders which blocks → SOUTHWESTERN BELL 9533 PARKIN AR
— 870-759 3XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → SOUTHWESTERN BELL 9533 WALNUT RDG AR
— 870-762 not yet reported which blocks → SOUTHWESTERN BELL 9533 BLYTHEVL AR
— 870-763 not yet reported which blocks → SOUTHWESTERN BELL 9533 BLYTHEVL AR
— 870-766 2XXX3XXX6XXX7XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 ALTHEIMER AR
— 870-768 0XXX2XXX3XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → SOUTHWESTERN BELL 9533 MORO AR
— 870-776 0XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 BLYTHEVL AR
— 870-777 not yet reported which blocks → SOUTHWESTERN BELL 9533 HOPE AR
— 870-780 not yet reported which blocks → SOUTHWESTERN BELL 9533 BLYTHEVL AR
— 870-786 2XXX3XXX7XXX8XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 STEPHENS AR
— 870-792 0XXX2XXX3XXX4XXX5XXX9XXX · 6 holders which blocks → SOUTHWESTERN BELL 9533 EARLE AR
— 870-793 not yet reported which blocks → SOUTHWESTERN BELL 9533 BATESVILLE AR
— 870-794 1XXX2XXX5XXX6XXX7XXX8XXX which blocks → SOUTHWESTERN BELL 9533 PINE BLUFF AR
— 870-797 none assigned yet which blocks → SOUTHWESTERN BELL 9533 STRONG AR
— 870-799 0XXX4XXX5XXX7XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 NEWARK AR
— 870-802 9XXX which blocks → SOUTHWESTERN BELL 9533 JONESBORO AR
— 870-816 4XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 HELENA AR
— 870-817 not yet reported which blocks → SOUTHWESTERN BELL 9533 HELENA AR
— 870-819 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 JONESBORO AR
— 870-823 0XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → SOUTHWESTERN BELL 9533 CRAWFODSVL AR
— 870-836 not yet reported which blocks → SOUTHWESTERN BELL 9533 CAMDEN AR
— 870-837 4XXX which blocks → SOUTHWESTERN BELL 9533 CAMDEN AR
— 870-838 0XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 BLYTHEVL AR
— 870-845 0XXX which blocks → SOUTHWESTERN BELL 9533 NASHVILLE AR
— 870-850 none assigned yet which blocks → SOUTHWESTERN BELL 9533 PINE BLUFF AR
— 870-853 3XXX which blocks → SOUTHWESTERN BELL 9533 HAMBURG AR
— 870-862 not yet reported which blocks → SOUTHWESTERN BELL 9533 EL DORADO AR
— 870-863 not yet reported which blocks → SOUTHWESTERN BELL 9533 EL DORADO AR
— 870-864 not yet reported which blocks → SOUTHWESTERN BELL 9533 EL DORADO AR
— 870-875 0XXX3XXX9XXX which blocks → SOUTHWESTERN BELL 9533 EL DORADO AR
— 870-877 0XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 ARKANSASCY AR
— 870-878 0XXX3XXX4XXX5XXX7XXX8XXX9XXX · 7 holders which blocks → SOUTHWESTERN BELL 9533 BLACK ROCK AR
— 870-879 none assigned yet which blocks → SOUTHWESTERN BELL 9533 PINE BLUFF AR
— 870-881 none assigned yet which blocks → SOUTHWESTERN BELL 9533 EL DORADO AR
— 870-886 0XXX8XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 WALNUT RDG AR
— 870-898 0XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 ASHDOWN AR
— 870-899 0XXX3XXX4XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 BODCAW AR
— 870-901 0XXX1XXX3XXX4XXX6XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 MAGNOLIA AR
— 870-910 not yet reported which blocks → SOUTHWESTERN BELL 9533 JONESBORO AR
— 870-930 not yet reported which blocks → SOUTHWESTERN BELL 9533 JONESBORO AR
— 870-931 not yet reported which blocks → SOUTHWESTERN BELL 9533 JONESBORO AR
— 870-932 not yet reported which blocks → SOUTHWESTERN BELL 9533 JONESBORO AR
— 870-933 not yet reported which blocks → SOUTHWESTERN BELL 9533 JONESBORO AR
— 870-934 not yet reported which blocks → SOUTHWESTERN BELL 9533 JONESBORO AR
— 870-935 not yet reported which blocks → SOUTHWESTERN BELL 9533 JONESBORO 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.