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: 537

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-537 A Tucson AZ TCSNAZMAXBY  515J IP HORIZON LLC 668      
520-537 0 Tucson AZ TCSNAZMAX3Y  624H ONVOY SPECTRUM, LLC 668   2021-05-22   
520-537 1 Tucson AZ   515J IP HORIZON LLC 668   2021-04-25   
520-537 2 Tucson AZ TCSNAZMAVMD  3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 668   2021-05-15   
520-537 3 Tucson AZ TCSNAZMAX3Y  624H ONVOY SPECTRUM, LLC 668   2021-05-22   
520-537 4 Tucson AZ TCSNAZMAX3Y  624H ONVOY SPECTRUM, LLC 668   2021-05-22   
520-537 5 Tucson AZ TCSMAZCHEMD  321J HD CARRIER LLC 668   2021-05-07   
520-537 6 Tucson AZ TCSMAZCHEMD  321J HD CARRIER LLC 668   2021-05-07   
520-537 7 Tucson AZ TCSMAZCHEMD  321J HD CARRIER LLC 668   2021-05-07   
520-537 8 Tucson AZ TCSMAZCHEMD  321J HD CARRIER LLC 668   2021-05-07   
520-537 9 Tucson AZ TCSMAZCHEMD  321J HD CARRIER LLC 668   2021-05-07   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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