NumberResearch Membership · Data 09/20/2026

Recent prefix assignments

5 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 435
UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS 4
TDS BROADBAND SERVICE LLC 1
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
Clear Download CSV ↓
Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
2021-07-01 435-600 0XXX1XXX3XXX6XXX8XXX9XXX · 4 holders which blocks → FRACTEL, LLC 965H PAROWAN UT
2021-07-01 435-667 0–9 XXXall 10 · 6 holders which blocks → FRACTEL, LLC 965H BRIGHAM CY UT
2021-04-26 435-309 0–9 XXXall 10 · 6 holders which blocks → ONVOY, LLC - UT 871E GLNCNYONCY UT
2021-04-18 435-297 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT 6571 KAMAS UT
2021-04-12 435-547 0XXX1XXX2XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → TON80 COMMUNICATIONS, LLC 516J BRIAN HEAD UT
2021-02-01 435-352 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT 6571 HEBER CITY UT
2021-01-28 435-302 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT 6571 KAMAS UT
2021-01-26 435-303 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT 6571 BEARRIV CY UT
2021-01-25 435-281 0–9 XXXall 10 · 4 holders which blocks → NUSO, LLC 478J WASATCH UT
2021-01-12 435-274 0–9 XXXall 10 · 5 holders which blocks → ONVOY, LLC - UT 871E TOOELE UT
2020-12-29 435-278 0XXX1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT 6571 ENTERPRISE UT
2020-11-24 435-523 0–9 XXXall 10 · 6 holders which blocks → ONVOY, LLC - UT 871E ST GEORGE UT
2020-11-09 435-534 0–9 XXXall 10 · 5 holders which blocks → ONVOY, LLC - UT 871E LOGAN UT
2020-10-07 435-290 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT 6571 KAMAS UT
2020-05-12 435-293 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT 6571 KAMAS UT
2020-04-20 435-334 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → ONVOY, LLC - UT 871E FILLMORE UT
2019-06-03 435-900 0–9 XXXall 10 · 5 holders which blocks → FRACTEL, LLC 965H ST GEORGE UT
2019-05-01 435-295 0–9 XXXall 10 · 6 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT 6571 BRIGHAM CY UT
2019-04-25 435-500 0–9 XXXall 10 · 5 holders which blocks → ONVOY, LLC - UT 871E DELTA UT
2019-03-06 435-296 0–9 XXXall 10 · 4 holders which blocks → PEERLESS NETWORK OF UTAH, LLC - UT 526H GLNCNYONCY UT
2019-03-05 435-271 0XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → PEERLESS NETWORK OF UTAH, LLC - UT 526H SALINA UT
2019-03-05 435-289 0–9 XXXall 10 · 7 holders which blocks → PEERLESS NETWORK OF UTAH, LLC - UT 526H RICHFIELD UT
2019-01-24 435-666 0–9 XXXall 10 · 7 holders which blocks → FRACTEL, LLC 965H PARK CITY UT
2019-01-23 435-264 0–9 XXXwhole prefix which blocks → ONVOY, LLC - UT 871E NAT BRIDGE UT
2019-01-23 435-269 0XXX1XXX2XXX3XXX4XXX5XXX9XXX · 2 holders which blocks → ONVOY, LLC - UT 871E BLUFF UT
2019-01-23 435-280 0XXX2XXX4XXX8XXX · 2 holders which blocks → ONVOY, LLC - UT 871E MEXICANHAT UT
2019-01-23 435-284 3XXX4XXX6XXX8XXX · 2 holders which blocks → ONVOY, LLC - UT 871E KANOSH UT
2019-01-23 435-325 2XXX3XXX4XXX5XXX8XXX which blocks → ONVOY, LLC - UT 871E MEADOW UT
2019-01-23 435-337 2XXX3XXX4XXX6XXX7XXX · 3 holders which blocks → ONVOY, LLC - UT 871E LAKEPOWELL UT
2019-01-23 435-344 0XXX2XXX3XXX4XXX5XXX · 2 holders which blocks → ONVOY, LLC - UT 871E LA SAL UT
2019-01-23 435-345 4XXX5XXX6XXX which blocks → ONVOY, LLC - UT 871E THOMPSON UT
2019-01-23 435-432 0XXX1XXX2XXX3XXX4XXX5XXX6XXX8XXX · 3 holders which blocks → ONVOY, LLC - UT 871E PROMONTORY UT
2019-01-23 435-441 1XXX2XXX3XXX4XXX5XXX which blocks → ONVOY, LLC - UT 871E HOLDEN UT
2019-01-23 435-495 2XXX4XXX5XXX which blocks → ONVOY, LLC - UT 871E OAK CITY UT
2018-12-20 435-375 0–9 XXXall 10 · 7 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 ST GEORGE UT
2018-12-17 435-395 0–9 XXXall 10 · 4 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 HEBER CITY UT
2018-10-19 435-254 0–9 XXXwhole prefix which blocks → ONVOY, LLC - UT 871E PORTAGE UT
2018-10-19 435-266 0–9 XXXall 10 · 2 holders which blocks → ONVOY, LLC - UT 871E LYNNDYL UT
2018-10-19 435-409 2XXX4XXX5XXX8XXX which blocks → ONVOY, LLC - UT 871E SCIPIO UT
2018-10-19 435-422 1XXX2XXX3XXX4XXX6XXX · 3 holders which blocks → ONVOY, LLC - UT 871E HOWELL UT
2018-10-19 435-447 0XXX4XXX7XXX which blocks → ONVOY, LLC - UT 871E FIELDING UT
2018-10-19 435-626 2XXX4XXX6XXX7XXX · 3 holders which blocks → ONVOY, LLC - UT 871E SNOWVILLE UT
2018-10-19 435-923 2XXX3XXX4XXX5XXX which blocks → ONVOY, LLC - UT 871E THATCHER UT
2018-09-28 435-244 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - UT 871E TOOELE UT
2018-04-10 435-466 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT 6571 BEARRIV CY UT
2017-11-16 435-522 0–9 XXXall 10 · 7 holders which blocks → CENTURYLINK COMMUNICATIONS, LLC 508J ST GEORGE UT
2017-08-31 435-800 0–9 XXXall 10 · 6 holders which blocks → ONVOY, LLC - UT 871E PARK CITY UT
2017-03-01 435-777 0–9 XXXall 10 · 8 holders which blocks → TELNYX LLC 073H HEBER CITY UT
2016-11-21 435-236 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT 6571 ST GEORGE UT
2016-04-28 435-205 none assigned yet which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 MNZMCRANTH UT

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.