NumberResearch Membership · Data 09/20/2026

Recent prefix assignments

2 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, last 30 days — NPA 307
UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS 2
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
— 307-242 1XXX4XXX5XXX6XXX8XXX · 2 holders which blocks → QWEST CORPORATION 9636 LAKE WY
— 307-243 0–9 XXXall 10 · 6 holders which blocks → ONVOY, LLC - WY 450F CASPER WY
— 307-245 not yet reported which blocks → RT COMMUNICATIONS 3410 PINEBLUFFS WY
— 307-246 not yet reported which blocks → RT COMMUNICATIONS 3410 ALBIN WY
— 307-247 6XXX7XXX8XXX9XXX · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 CASPER WY
— 307-250 9XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 6566 CODY WY
— 307-252 not yet reported which blocks → UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS 1772 ROCK SPG WY
— 307-258 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 6566 CASPER WY
— 307-259 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 6566 CASPER WY
— 307-260 not yet reported which blocks → UNION TELEPHONE COMPANY 013B BIG PINEY WY
— 307-261 not yet reported which blocks → QWEST CORPORATION 9636 CASPER WY
— 307-262 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 6566 CASPER WY
— 307-265 not yet reported which blocks → QWEST CORPORATION 9636 CASPER WY
— 307-266 not yet reported which blocks → QWEST CORPORATION 9636 CASPER WY
— 307-267 none assigned yet which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 CASPER WY
— 307-268 not yet reported which blocks → QWEST CORPORATION 9636 CASPER WY
— 307-269 0–9 XXXall 10 · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WY 9416 WHEATLAND WY
— 307-270 not yet reported which blocks → UNION TELEPHONE COMPANY 013B COKEVILLE WY
— 307-272 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 6566 CODY WY
— 307-273 1XXX which blocks → CENTURYTEL OF WYOMING, INC. DBA CENTURYLINK 2299 FARSON WY
— 307-276 1XXX which blocks → CENTURYTEL OF WYOMING, INC. DBA CENTURYLINK 2299 BIG PINEY WY
— 307-279 not yet reported which blocks → ALL WEST COMMUNICATIONS - WY 2290 COKEVILLE WY
— 307-280 not yet reported which blocks → UNION TELEPHONE COMPANY 013B FARSON WY
— 307-281 5XXX6XXX7XXX · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 6566 SUNDANCE WY
— 307-282 none assigned yet which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 6566 SUNDANCE WY
— 307-283 not yet reported which blocks → RANGE TEL COOP INC 2251 SUNDANCE WY
— 307-290 4XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 SUNDANCE WY
— 307-296 0–9 XXXall 10 · 5 holders which blocks → ONVOY, LLC - WY 450F CODY WY
— 307-297 not yet reported which blocks → UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS 1772 GREENRIVER WY
— 307-307 not yet reported which blocks → WY
— 307-308 not yet reported which blocks → WY
— 307-311 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX WY
— 307-313 0–9 XXXall 10 · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WY 9416 EVANSTON WY
— 307-314 0–9 XXXall 10 · 5 holders which blocks → BANDWIDTH.COM CLEC, LLC - WY 081F LARAMIE WY
— 307-320 not yet reported which blocks → UNION TELEPHONE COMPANY 013B RAWLINS WY
— 307-321 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 6566 RAWLINS WY
— 307-322 not yet reported which blocks → QWEST CORPORATION 9636 WHEATLAND WY
— 307-324 not yet reported which blocks → QWEST CORPORATION 9636 RAWLINS WY
— 307-325 not yet reported which blocks → UNION TEL. CO. 2297 HANNA WY
— 307-326 not yet reported which blocks → UNION TEL. CO. 2297 SARATOGA WY
— 307-327 not yet reported which blocks → UNION TEL. CO. 2297 ENCAMPMENT WY
— 307-328 5XXX which blocks → QWEST CORPORATION 9636 RAWLINS WY
— 307-329 not yet reported which blocks → UNION TELEPHONE COMPANY 013B SARATOGA WY
— 307-330 not yet reported which blocks → UNION TELEPHONE COMPANY 013B LANDER WY
— 307-331 6XXX7XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 6566 WHEATLAND WY
— 307-332 not yet reported which blocks → QWEST CORPORATION 9636 LANDER WY
— 307-333 0–9 XXXall 10 · 4 holders which blocks → NUSO, LLC 732J CASPER WY
— 307-334 1XXX which blocks → QWEST CORPORATION 9636 LUSK WY
— 307-335 1XXX3XXX4XXX5XXX · 3 holders which blocks → QWEST CORPORATION 9636 LANDER WY
— 307-339 not yet reported which blocks → UNION TELEPHONE COMPANY 013B HANNA WY

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.