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 440
WINDSTREAM WESTERN RESERVE, INC. 39
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
2013-06-06 440-805 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 ROCK CREEK OH
2011-09-16 440-214 0–9 XXXall 10 · 7 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 CHARDON OH
2011-09-16 440-261 0–9 XXXall 10 · 8 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 ASHTABULA OH
2011-09-16 440-307 0–9 XXXall 10 · 6 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 MADISON OH
2001-05-22 440-271 1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 5 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 PARKMAN OH
— 440-206 6XXX7XXX8XXX which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 AUSTINBURG OH
— 440-224 4XXX8XXX · 2 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 KINGSVILLE OH
— 440-259 6XXX7XXX8XXX · 2 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 PERRY OH
— 440-275 5XXX which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 AUSTINBURG OH
— 440-279 3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 CHARDON OH
— 440-280 0XXX1XXX2XXX · 2 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 PERRY OH
— 440-285 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 CHARDON OH
— 440-286 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 CHARDON OH
— 440-298 2XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 THOMPSON OH
— 440-338 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 RUSSELL OH
— 440-415 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 GENEVA OH
— 440-417 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 MADISON OH
— 440-428 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 MADISON OH
— 440-466 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 GENEVA OH
— 440-474 2XXX3XXX which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 TRUMBULL OH
— 440-543 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 BAINBRIDGE OH
— 440-548 1XXX which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 PARKMAN OH
— 440-563 1XXX2XXX6XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 ROCK CREEK OH
— 440-564 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 NEWBURY OH
— 440-577 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 PIERPONT OH
— 440-632 4XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 MIDDLEFLD OH
— 440-635 3XXX6XXX7XXX · 3 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 E CLARIDON OH
— 440-636 0XXX1XXX2XXX3XXX4XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 HUNTSBURG OH
— 440-693 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 MESOPOTMIA OH
— 440-708 3XXX4XXX6XXX7XXX8XXX · 2 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 BAINBRIDGE OH
— 440-858 1XXX3XXX4XXX5XXX6XXX7XXX · 3 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 DORSET OH
— 440-964 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 ASHTABULA OH
— 440-968 1XXX2XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 MONTVILLE OH
— 440-969 0XXX3XXX4XXX5XXX6XXX8XXX · 3 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 ASHTABULA OH
— 440-992 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 ASHTABULA OH
— 440-993 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 ASHTABULA OH
— 440-994 0XXX4XXX · 2 holders which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 ASHTABULA OH
— 440-997 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 ASHTABULA OH
— 440-998 not yet reported which blocks → WINDSTREAM WESTERN RESERVE, INC. 0666 ASHTABULA OH

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.