Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 920 [Rate centres in NPA 920] [Dial plan for NPA 920]

NXX: 523

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
920-523 A Cascade WI MILWWIDK6MD  5489 LEVEL 3 COMMUNICATIONS, LLC - WI 356      
920-523 1 Cascade WI   5489 LEVEL 3 COMMUNICATIONS, LLC - WI 356   2005-09-10   
920-523 2 Cascade WI   225C ONVOY, LLC - WI 356   2021-04-08   
920-523 3 Cascade WI   225C ONVOY, LLC - WI 356   2021-04-08   
920-523 4 Cascade WI   5489 LEVEL 3 COMMUNICATIONS, LLC - WI 356      
920-523 6 Cascade WI   793K TWC IP ENABLED SERVICES, LLC 356   2007-03-27   
920-523 7 Cascade WI   508J CENTURYLINK COMMUNICATIONS, LLC 356   2015-01-02   
920-523 8 Cascade WI   624H ONVOY SPECTRUM, LLC 356   2021-06-25   
920-523 9 Cascade WI   007F BANDWIDTH.COM CLEC, LLC - WI 356   2008-11-22   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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