Recent prefix assignments

5 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/19/2026

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

Recent NPA-NXX prefix assignments
Assigned	NPA-NXX	Thousands-blocks taken (last-4 opening)	Code holder	OCN	Rate center	State
2026-09-15	435-377	2XXX which blocks →	TDS BROADBAND SERVICE LLC	641H	ST GEORGE	UT
2026-09-10	435-370	0–9 XXXwhole prefix which blocks →	UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS	1772	DUTCH JOHN	UT
2026-09-10	435-371	0–9 XXXwhole prefix which blocks →	UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS	1772	MANILA	UT
2026-09-08	435-367	0–9 XXXwhole prefix which blocks →	UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS	1772	LAPOINT	UT
2026-09-08	435-376	0–9 XXXwhole prefix which blocks →	UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS	1772	FRUITLAND	UT
2026-05-05	435-407	0–9 XXXwhole prefix which blocks →	UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS	1772	TABIONA	UT
2026-05-05	435-408	0–9 XXXwhole prefix which blocks →	UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS	1772	ALTAMONT	UT
2026-05-05	435-410	0–9 XXXwhole prefix which blocks →	UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS	1772	RANDLETT	UT
2025-12-03	435-369	7XXX9XXX · 2 holders which blocks →	T-MOBILE USA, INC.	6529	BRIGHAM CY	UT
2025-09-18	435-368	0XXX1XXX · 2 holders which blocks →	ONVOY, LLC - UT	871E	LOGAN	UT
2025-09-12	435-366	0–9 XXXall 10 · 5 holders which blocks →	TDS BROADBAND SERVICE LLC	641H	ST GEORGE	UT
2025-08-28	435-365	6XXX7XXX8XXX9XXX which blocks →	T-MOBILE USA, INC.	6529	HEBER CITY	UT
2025-03-03	435-362	0XXX which blocks →	E. FIBER MOAB, LLC	831J	THOMPSON	UT
2024-10-17	435-346	0XXX1XXX8XXX · 2 holders which blocks →	CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT	6571	PARK CITY	UT
2024-05-31	435-360	0–9 XXXall 10 · 4 holders which blocks →	T-MOBILE USA, INC.	6529	ST GEORGE	UT
2024-05-23	435-328	1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks →	T-MOBILE USA, INC.	6529	HEBER CITY	UT
2024-03-18	435-361	0–9 XXXall 10 · 5 holders which blocks →	ONVOY, LLC - UT	871E	LOGAN	UT
2023-09-21	435-358	0XXX1XXX2XXX5XXX7XXX8XXX which blocks →	CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT	6571	COALVILLE	UT
2023-09-06	435-357	0–9 XXXall 10 · 6 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	ST GEORGE	UT
2023-08-09	435-354	0XXX1XXX2XXX3XXX5XXX8XXX9XXX · 3 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	TOOELE	UT
2023-04-11	435-351	0–9 XXXall 10 · 2 holders which blocks →	ONVOY, LLC - UT	871E	ST GEORGE	UT
2023-02-10	435-350	0–9 XXXwhole prefix which blocks →	CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT	6571	COALVILLE	UT
2023-02-01	435-332	2XXX9XXX · 2 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	HANKSVILLE	UT
2023-02-01	435-342	9XXX which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	DNGLNG RPE	UT
2023-02-01	435-343	3XXX9XXX · 2 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	MANILA	UT
2023-01-27	435-329	9XXX which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	BOULDER	UT
2023-01-27	435-330	0XXX9XXX · 2 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	CANNONVL	UT
2023-01-27	435-331	1XXX9XXX · 2 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	DUCK CREEK	UT
2022-06-29	435-288	0–9 XXXall 10 · 4 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	ST GEORGE	UT
2022-02-24	435-567	0XXX1XXX3XXX4XXX6XXX7XXX8XXX9XXX · 7 holders which blocks →	TON80 COMMUNICATIONS, LLC	516J	RICHFIELD	UT
2022-02-24	435-569	0XXX6XXX · 2 holders which blocks →	TON80 COMMUNICATIONS, LLC	516J	MOAB	UT
2022-01-31	435-341	0XXX1XXX4XXX8XXX · 4 holders which blocks →	BANDWIDTH.COM CLEC, LLC - UT	117F	MONROE	UT
2022-01-27	435-737	1XXX2XXX5XXX7XXX8XXX9XXX · 6 holders which blocks →	TON80 COMMUNICATIONS, LLC	516J	TOOELE	UT
2022-01-27	435-746	0XXX1XXX2XXX3XXX4XXX7XXX · 2 holders which blocks →	TON80 COMMUNICATIONS, LLC	516J	KAMAS	UT
2021-12-17	435-317	0–9 XXXall 10 · 8 holders which blocks →	BOOST SUBSCRIBERCO L.L.C.	490J	LOGAN	UT
2021-11-24	435-270	0XXX1XXX4XXX · 2 holders which blocks →	E. FIBER SAN JUAN, LLC	832J	BLANDING	UT
2021-11-24	435-298	8XXX which blocks →	E. FIBER SAN JUAN, LLC	832J	MONTICELLO	UT
2021-11-12	435-306	9XXX which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	EUREKA	UT
2021-11-12	435-318	9XXX which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	IBAPAH	UT
2021-11-12	435-323	3XXX7XXX9XXX · 3 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	PARKVALLEY	UT
2021-10-14	435-321	0–9 XXXwhole prefix which blocks →	CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT	6571	KAMAS	UT
2021-09-24	435-312	not yet reported which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	HALCHITA	UT
2021-09-24	435-320	not yet reported which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	MNZMCRANTH	UT
2021-09-16	435-824	not yet reported which blocks →	UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS	1772	NEOLA	UT
2021-08-12	435-599	0–9 XXXall 10 · 4 holders which blocks →	FRACTEL, LLC	965H	ST GEORGE	UT
2021-08-12	435-699	0–9 XXXall 10 · 5 holders which blocks →	FRACTEL, LLC	965H	PARK CITY	UT
2021-07-21	435-308	9XXX which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	MONUMNTVLY	UT
2021-07-16	435-732	0XXX1XXX2XXX4XXX5XXX8XXX9XXX · 4 holders which blocks →	FRACTEL, LLC	965H	TREMONTON	UT
2021-07-01	435-348	0XXX1XXX2XXX6XXX8XXX9XXX · 3 holders which blocks →	FRACTEL, LLC	965H	FILLMORE	UT
2021-07-01	435-356	4XXX5XXX6XXX7XXX9XXX · 3 holders which blocks →	FRACTEL, LLC	965H	DELTA	UT

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.