Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 520 [Rate centres in NPA 520] [Dial plan for NPA 520]

NXX: 556

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-556 A Sierra Vista AZ TCSMAZOI3MD  6529 T-MOBILE USA, INC. 668      
520-556 0 Sierra Vista AZ TCSNAZMAX3Y  624H ONVOY SPECTRUM, LLC 668      
520-556 1 Sierra Vista AZ   515J IP HORIZON LLC 668      
520-556 2 Sierra Vista AZ TCSNAZMAX3Y  624H ONVOY SPECTRUM, LLC 668      
520-556 3 Sierra Vista AZ TCSNAZMAX3Y  624H ONVOY SPECTRUM, LLC 668      
520-556 4 Sierra Vista AZ TCSNAZMAXHX  630E ONVOY, LLC - AZ 668      
520-556 5 Sierra Vista AZ TCSNAZMAXHX  630E ONVOY, LLC - AZ 668      
520-556 6 Sierra Vista AZ TCSNAZMAXHX  630E ONVOY, LLC - AZ 668      
520-556 7 Sierra Vista AZ TCSNAZMAXHX  630E ONVOY, LLC - AZ 668      
520-556 8 Sierra Vista AZ TCSNAZMAXHX  630E ONVOY, LLC - AZ 668      
520-556 9 Sierra Vista AZ TCSMAZOI3MD  6529 T-MOBILE USA, INC. 668      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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