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: 304

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
435-304 A Richfield UT WVCYUTBXDS0  7530 TELEPORT COMMUNICATIONS AMERICA, LLC - UT 660      
435-304 0 Richfield UT   7530 TELEPORT COMMUNICATIONS AMERICA, LLC - UT 660      
435-304 1 Richfield UT   7530 TELEPORT COMMUNICATIONS AMERICA, LLC - UT 660      
435-304 2 Richfield UT   145J TERRA NOVA TELECOM INC. 660   2026-03-04   
435-304 4 Richfield UT   7530 TELEPORT COMMUNICATIONS AMERICA, LLC - UT 660      
435-304 6 Richfield UT   871E ONVOY, LLC - UT 660   2012-12-20   
435-304 9 Richfield UT   7530 TELEPORT COMMUNICATIONS AMERICA, LLC - UT 660      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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