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 CINGULAR WIRELESS PCS, LLC - IL 86
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AR 54
LEVEL 3 COMMUNICATIONS, LLC - AR 48
T-MOBILE USA, INC. 42
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
— 501-354 not yet reported which blocks → SOUTHWESTERN BELL 9533 MORRILTON AR
— 501-355 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → LEVEL 3 TELECOM OF ARKANSAS, LLC - AR 7264 LITTLEROCK AR
— 501-358 0–9 XXXall 10 · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - AR 5179 CONWAY AR
— 501-359 0–9 XXXall 10 · 3 holders which blocks → E. RITTER COMMUNICATIONS, LLC 128L HOTSPRINGS AR
— 501-360 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 LITTLEROCK AR
— 501-362 not yet reported which blocks → SOUTHWESTERN BELL 9533 HEBER SPG AR
— 501-364 not yet reported which blocks → WINDSTREAM COMMUNICATIONS, INC. - AR 7656 LITTLEROCK AR
— 501-367 3XXX4XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → WINDSTREAM COMMUNICATIONS, INC. - AR 7656 PINNACLE AR
— 501-368 5XXX8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 SEARCY AR
— 501-370 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-371 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-372 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-373 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-374 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-375 none assigned yet which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-376 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-377 9XXX which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-378 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-379 0XXX6XXX8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-380 0–9 XXXall 10 · 5 holders which blocks → SOUTHWESTERN BELL 9533 SEARCY AR
— 501-384 not yet reported which blocks → CENTRAL ARKANSAS TEL. COOP., INC. 1697 DONALDSON AR
— 501-390 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 LITTLEROCK AR
— 501-392 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → WINDSTREAM COMMUNICATIONS, INC. - AR 7656 SYVNHLSHWD AR
— 501-395 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 LITTLEROCK AR
— 501-396 6XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-397 0XXX1XXX3XXX4XXX8XXX9XXX · 2 holders which blocks → BRIGHTSPEED OF SOUTH CENTRAL ARKANSAS, LLC 1720 REDFIELD AR
— 501-399 4XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-401 1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → VONAGE AMERICA LLC 197D LITTLEROCK AR
— 501-405 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 LITTLEROCK AR
— 501-407 1XXX4XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-411 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX AR
— 501-412 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 LITTLEROCK AR
— 501-413 2XXX3XXX4XXX5XXX6XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 LITTLEROCK AR
— 501-416 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 LITTLEROCK AR
— 501-421 not yet reported which blocks → LEVEL 3 COMMUNICATIONS, LLC - AR 5179 LITTLEROCK AR
— 501-423 not yet reported which blocks → LEVEL 3 COMMUNICATIONS, LLC - AR 5179 LITTLEROCK AR
— 501-425 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 LITTLEROCK AR
— 501-432 2XXX3XXX4XXX7XXX9XXX · 4 holders which blocks → WINDSTREAM ARKANSAS, INC. 1691 NIMROD AR
— 501-433 not yet reported which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-440 4XXX5XXX7XXX8XXX · 4 holders which blocks → WINDSTREAM ARKANSAS, INC. 1691 SO FOURCHE AR
— 501-448 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → WINDSTREAM COMMUNICATIONS, INC. - AR 7656 FERNDALE AR
— 501-450 not yet reported which blocks → SOUTHWESTERN BELL 9533 CONWAY AR
— 501-454 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 LITTLEROCK AR
— 501-455 9XXX which blocks → SOUTHWESTERN BELL 9533 LITTLEROCK AR
— 501-457 1XXX2XXX3XXX4XXX6XXX7XXX9XXX · 4 holders which blocks → WINDSTREAM COMMUNICATIONS, INC. - AR 7656 JACKSONVL AR
— 501-463 0–9 XXXall 10 · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - AR 5179 HOTSPRINGS AR
— 501-465 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 CONWAY AR
— 501-467 1XXX2XXX4XXX5XXX6XXX7XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 MALVERN AR
— 501-469 0XXX1XXX2XXX4XXX7XXX9XXX · 4 holders which blocks → ONVOY SPECTRUM, LLC 624H BIGELOW AR
— 501-470 5XXX6XXX7XXX8XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 CONWAY 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.