Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 435 [Rate centres in NPA 435] [Dial plan for NPA 435]

NXX: 621

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
435-621 A Vernal UT DRPRUTKJ0MD  6529 T-MOBILE USA, INC. 660      
435-621 0 Vernal UT   6529 T-MOBILE USA, INC. 660   2024-02-18   
435-621 1 Vernal UT   6010 NEW CINGULAR WIRELESS PCS, LLC 660   2005-08-01   
435-621 2 Vernal UT   6010 NEW CINGULAR WIRELESS PCS, LLC 660   2006-03-20   
435-621 3 Vernal UT   6010 NEW CINGULAR WIRELESS PCS, LLC 660   2006-07-28   
435-621 4 Vernal UT   6010 NEW CINGULAR WIRELESS PCS, LLC 660   2006-07-28   
435-621 5 Vernal UT   6010 NEW CINGULAR WIRELESS PCS, LLC 660   2006-07-28   
435-621 6 Vernal UT   5562 METROPCS, INC. 660   2004-10-03   
435-621 7 Vernal UT   6529 T-MOBILE USA, INC. 660   2004-10-03   
435-621 8 Vernal UT   6010 NEW CINGULAR WIRELESS PCS, LLC 660   2006-07-28   
435-621 9 Vernal UT   145J TERRA NOVA TELECOM INC. 660   2025-07-10   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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