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 281
SOUTHWESTERN BELL 283
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TX 66
FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 57
NEW CINGULAR WIRELESS PCS, LLC - IL 50
WINDSTREAM SUGAR LAND, LLC 38
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
— 281-253 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TX 6506 LANGHAMCRK TX
— 281-255 not yet reported which blocks → SOUTHWESTERN BELL 9533 TOMBALL TX
— 281-256 5XXX which blocks → SOUTHWESTERN BELL 9533 CYPRESS TX
— 281-257 not yet reported which blocks → SOUTHWESTERN BELL 9533 TOMBALL TX
— 281-259 not yet reported which blocks → SOUTHWESTERN BELL 9533 PINEHURST TX
— 281-260 not yet reported which blocks → SOUTHWESTERN BELL 9533 HSTNSUBURB TX
— 281-261 not yet reported which blocks → FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 4344 STAFFORD TX
— 281-262 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-263 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-264 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-265 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-266 not yet reported which blocks → SPOK, INC. 6630 HOUSTON TX
— 281-267 not yet reported which blocks → SPOK, INC. 6630 HOUSTON TX
— 281-268 not yet reported which blocks → SPOK, INC. 6630 HOUSTON TX
— 281-269 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-271 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 DEER PARK TX
— 281-272 3XXX6XXX8XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 HSTNSUBURB TX
— 281-273 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-274 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-275 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-276 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-277 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-278 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-279 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-280 not yet reported which blocks → SOUTHWESTERN BELL 9533 APOLLO TX
— 281-282 7XXX8XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 APOLLO TX
— 281-283 not yet reported which blocks → SOUTHWESTERN BELL 9533 APOLLO TX
— 281-284 not yet reported which blocks → SOUTHWESTERN BELL 9533 APOLLO TX
— 281-285 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-286 not yet reported which blocks → SOUTHWESTERN BELL 9533 APOLLO TX
— 281-287 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-288 not yet reported which blocks → SOUTHWESTERN BELL 9533 SPRING TX
— 281-289 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-290 4XXX which blocks → SOUTHWESTERN BELL 9533 TOMBALL TX
— 281-291 not yet reported which blocks → SOUTHWESTERN BELL 9533 SEABROOK TX
— 281-292 not yet reported which blocks → SOUTHWESTERN BELL 9533 SPRING TX
— 281-293 not yet reported which blocks → SOUTHWESTERN BELL 9533 HSTNSUBURB TX
— 281-294 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-295 not yet reported which blocks → WINDSTREAM SUGAR LAND, LLC 2147 SUGAR LAND TX
— 281-296 3XXX which blocks → SOUTHWESTERN BELL 9533 SPRING TX
— 281-297 8XXX which blocks → SOUTHWESTERN BELL 9533 SPRING TX
— 281-298 not yet reported which blocks → SOUTHWESTERN BELL 9533 SPRING TX
— 281-299 0–9 XXXall 10 · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TX 6506 ALVIN TX
— 281-300 none assigned yet which blocks → METROPCS, INC. 5562 HOUSTON TX
— 281-301 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → GRANDE COMMUNICATIONS NETWORKS, INC. - TX 7670 BAMMEL TX
— 281-302 1XXX2XXX4XXX5XXX6XXX8XXX9XXX · 4 holders which blocks → GRANDE COMMUNICATIONS NETWORKS, INC. - TX 7670 SUGAR LAND TX
— 281-303 1XXX3XXX5XXX6XXX7XXX9XXX · 2 holders which blocks → FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 4344 BEACH CITY TX
— 281-304 2XXX3XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 CYPRESS TX
— 281-307 0XXX5XXX6XXX · 2 holders which blocks → ONVOY, LLC - TX 903C LA PORTE TX
— 281-308 not yet reported which blocks → TELETOUCH COMMUNICATIONS, INC. 6591 BAMMEL 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.