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
2015-12-18	435-305	9XXX which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	JORDANELLE	UT
2015-11-17	435-922	0–9 XXXall 10 · 7 holders which blocks →	BANDWIDTH.COM CLEC, LLC - UT	117F	ST GEORGE	UT
2015-09-30	435-268	0–9 XXXall 10 · 8 holders which blocks →	FIRSTDIGITAL COMMUNICATIONS, LLC	716D	TOOELE	UT
2015-06-04	435-557	0–9 XXXall 10 · 7 holders which blocks →	BANDWIDTH.COM CLEC, LLC - UT	117F	LOGAN	UT
2015-05-01	435-222	0–9 XXXall 10 · 6 holders which blocks →	BANDWIDTH.COM CLEC, LLC - UT	117F	HEBER CITY	UT
2015-03-12	435-217	9XXX which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	RANDOLPH	UT
2015-02-02	435-429	0–9 XXXall 10 · 3 holders which blocks →	BANDWIDTH.COM CLEC, LLC - UT	117F	ST GEORGE	UT
2015-01-28	435-515	0–9 XXXall 10 · 6 holders which blocks →	BANDWIDTH.COM CLEC, LLC - UT	117F	BRIGHAM CY	UT
2015-01-22	435-465	0–9 XXXall 10 · 7 holders which blocks →	MCIMETRO ACCESS TRANSMISSION SERVICES LLC	7229	BRIGHAM CY	UT
2014-07-08	435-255	0–9 XXXall 10 · 5 holders which blocks →	METROPCS, INC.	5562	TOOELE	UT
2014-07-08	435-265	0–9 XXXall 10 · 5 holders which blocks →	METROPCS, INC.	5562	LOGAN	UT
2014-02-06	435-223	not yet reported which blocks →	SOUTH CENTRAL COMM -TELCOM SERVICES, LLC UT	380F	BRIAN HEAD	UT
2013-05-16	435-218	0–9 XXXall 10 · 3 holders which blocks →	ONVOY, LLC - UT	871E	ST GEORGE	UT
2012-11-16	435-315	0–9 XXXall 10 · 7 holders which blocks →	COMCAST IP PHONE, LLC	318J	HEBER CITY	UT
2012-08-15	435-339	0–9 XXXall 10 · 5 holders which blocks →	T-MOBILE USA, INC.	6529	BRIGHAM CY	UT
2012-03-28	435-316	none assigned yet which blocks →	NAVAJO COMM CO INC - UT DBA NAVAJO COMM UT	4451	MONUMNTVLY	UT
2012-03-05	435-355	0–9 XXXall 10 · 5 holders which blocks →	EMERY TELECOMMUNICATIONS & VIDEO, INC. - UT	683H	MOAB	UT
2011-11-21	435-414	0–9 XXXall 10 · 5 holders which blocks →	T-MOBILE USA, INC.	6529	ST GEORGE	UT
2011-09-19	435-319	0–9 XXXall 10 · 4 holders which blocks →	T-MOBILE USA, INC.	6529	ST GEORGE	UT
2011-07-06	435-549	0–9 XXXall 10 · 4 holders which blocks →	T-MOBILE USA, INC.	6529	VERNAL	UT
2011-03-22	435-485	0–9 XXXall 10 · 4 holders which blocks →	CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT	6571	BLANDING	UT
2011-02-09	435-299	0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks →	CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT	6571	PRICE	UT
2011-01-27	435-525	0–9 XXXall 10 · 3 holders which blocks →	T-MOBILE USA, INC.	6529	ST GEORGE	UT
2010-10-18	435-322	0XXX2XXX3XXX · 3 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	DUCHESNE	UT
2010-07-23	435-314	0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks →	T-MOBILE USA, INC.	6529	EPHRAIM	UT
2010-05-28	435-243	0–9 XXXall 10 · 3 holders which blocks →	TELEPORT COMMUNICATIONS AMERICA, LLC - UT	7530	TOOELE	UT
2009-07-20	435-603	0XXX6XXX which blocks →	TELEPORT COMMUNICATIONS AMERICA, LLC - UT	7530	LOGAN	UT
2009-07-06	435-263	0–9 XXXall 10 · 2 holders which blocks →	SOUTH CENTRAL COMM -TELCOM SERVICES, LLC UT	380F	CEDAR CITY	UT
2009-02-26	435-364	not yet reported which blocks →	MANTI TELE COMMUNICATIONS COMPANY, INC.	441F	MANTI	UT
2008-03-18	435-287	0–9 XXXall 10 · 6 holders which blocks →	CENTRAL TELCOM SVCS DBA CENTRACOM INTERACTIVE - NV	791D	RICHFIELD	UT
2008-02-25	435-401	0XXX1XXX2XXX3XXX4XXX5XXX8XXX · 3 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	ROOSEVELT	UT
2007-10-25	435-374	0–9 XXXall 10 · 3 holders which blocks →	T-MOBILE USA, INC.	6529	LOGAN	UT
2007-10-18	435-412	0–9 XXXall 10 · 3 holders which blocks →	ONVOY, LLC - UT	871E	GLNCNYONCY	UT
2007-08-23	435-291	1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	TREMONTON	UT
2007-07-12	435-219	0–9 XXXall 10 · 2 holders which blocks →	T-MOBILE USA, INC.	6529	VERNAL	UT
2007-04-24	435-292	0–9 XXXall 10 · 3 holders which blocks →	ONVOY, LLC - UT	871E	WASATCH	UT
2006-12-20	435-282	1XXX2XXX4XXX · 2 holders which blocks →	T-MOBILE USA, INC.	6529	TREMONTON	UT
2006-09-08	435-393	0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	PAROWAN	UT
2006-05-17	435-444	not yet reported which blocks →	SMITH BAGLEY INC. DBA CELLULAR ONE OF NE ARIZONA	4146	MNZMCRANTH	UT
2006-04-14	435-277	0–9 XXXall 10 · 3 holders which blocks →	QWEST CORPORATION	9636	TOOELE	UT
2005-12-20	435-249	0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 4 holders which blocks →	COMCAST IP PHONE, LLC	318J	TOOELE	UT
2005-09-12	435-817	0–9 XXXall 10 · 3 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	ST GEORGE	UT
2005-09-06	435-400	1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks →	CELLCO PARTNERSHIP DBA VERIZON WIRELESS - UT	6571	COALVILLE	UT
2004-12-10	435-491	0XXX1XXX2XXX7XXX9XXX which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	BICKNELL	UT
2004-11-30	435-209	0XXX1XXX7XXX8XXX9XXX · 2 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	MILFORD	UT
2004-11-30	435-212	0XXX1XXX2XXX3XXX4XXX6XXX8XXX · 3 holders which blocks →	NEW CINGULAR WIRELESS PCS, LLC	6010	HILDALE	UT
2004-08-12	435-621	0–9 XXXall 10 · 4 holders which blocks →	T-MOBILE USA, INC.	6529	VERNAL	UT
2004-04-29	435-766	not yet reported which blocks →	UNION TELEPHONE COMPANY	013B	VERNAL	UT
2004-04-29	435-768	not yet reported which blocks →	UNION TELEPHONE COMPANY	013B	DUCHESNE	UT
2004-02-12	435-202	not yet reported which blocks →	UNION TELEPHONE COMPANY	013B	LOGAN	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.