NumberResearch Membership · Data 09/25/2026

Recent prefix assignments

337 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/25/2026

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, last 30 days
8X8, INC. 43
NEW CINGULAR WIRELESS PCS, LLC - DC 28
ONVOY, LLC - CA 26
NEW CINGULAR WIRELESS PCS, LLC - IL 25
U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 12
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
— 279-209 0–9 XXXall 10 · 4 holders which blocks → TWILIO INTERNATIONAL, INC. 506J ELK GROVE CA
— 279-210 0–9 XXXall 10 · 5 holders which blocks → T-MOBILE USA, INC. 6529 SCRM MAIN CA
— 279-211 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 279-231 0–9 XXXall 10 · 4 holders which blocks → NUSO, LLC 732J SCRM MAIN CA
— 279-233 0–9 XXXall 10 · 4 holders which blocks → NUSO, LLC 732J SCRM NORTH CA
— 279-311 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 279-321 0–9 XXXall 10 · 6 holders which blocks → ONVOY, LLC - CA 649C FOLSOM CA
— 279-411 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 279-511 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 279-555 not yet reported which blocks → MULTIPLE OCN LISTING MULT DIR ASST CA
— 279-611 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 279-700 not yet reported which blocks → CA
— 279-711 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 279-811 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 279-911 not yet reported which blocks → MULTIPLE OCN LISTING MULT CA
— 279-950 not yet reported which blocks → CA
— 279-958 not yet reported which blocks → CA
— 279-959 not yet reported which blocks → CA
— 279-976 not yet reported which blocks → CA
— 281-200 1XXX4XXX5XXX7XXX8XXX · 2 holders which blocks → ONVOY, LLC - TX 903C LANGHAMCRK TX
— 281-201 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → AT&T - LOCAL 7421 SUGAR LAND TX
— 281-202 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - TX 7138 RICHMNRNBG TX
— 281-203 0XXX1XXX2XXX4XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - TX 7138 SPRING TX
— 281-204 2XXX3XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - TX 7138 APOLLO TX
— 281-205 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - TX 7138 TOMBALL TX
— 281-206 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → AT&T - LOCAL 7421 BARKER TX
— 281-207 6XXX8XXX9XXX · 2 holders which blocks → LEVEL 3 OF TELECOM OF TEXAS, LLC - TX 7074 SUGAR LAND TX
— 281-208 7XXX which blocks → FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 4344 STAFFORD TX
— 281-209 5XXX which blocks → SOUTHWESTERN BELL 9533 WESTFIELD TX
— 281-210 4XXX6XXX7XXX8XXX9XXX which blocks → LEVEL 3 OF TELECOM OF TEXAS, LLC - TX 7074 SPRING TX
— 281-211 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX TX
— 281-212 0XXX3XXX4XXX7XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 APOLLO TX
— 281-213 0XXX2XXX4XXX5XXX7XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 CYPRESS TX
— 281-214 0XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - TX 6114 WESTFIELD TX
— 281-215 3XXX4XXX5XXX · 3 holders which blocks → ONVOY, LLC - TX 903C SHELDON TX
— 281-216 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 HOUSTON TX
— 281-217 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 HOUSTON TX
— 281-218 8XXX which blocks → SOUTHWESTERN BELL 9533 APOLLO TX
— 281-219 5XXX7XXX8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 HSTNSUBURB TX
— 281-220 1XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → GRANDE COMMUNICATIONS NETWORKS, INC. - TX 7670 HOUSTON TX
— 281-221 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 HOUSTON TX
— 281-222 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 HOUSTON TX
— 281-224 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 HOUSTON TX
— 281-225 not yet reported which blocks → ETS TELEPHONE COMPANY, INC. 2091 HOUSTON TX
— 281-226 0XXX2XXX3XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 APOLLO TX
— 281-227 not yet reported which blocks → SOUTHWESTERN BELL 9533 HSTNSUBURB TX
— 281-228 not yet reported which blocks → SOUTHWESTERN BELL 9533 HOUSTON TX
— 281-230 not yet reported which blocks → SOUTHWESTERN BELL 9533 WESTFIELD TX
— 281-232 not yet reported which blocks → SOUTHWESTERN BELL 9533 RICHMNRNBG TX
— 281-233 not yet reported which blocks → SOUTHWESTERN BELL 9533 WESTFIELD TX

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/25/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.