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: 537

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
920-537 A Horicon WI MILWWIAUDS1  225C ONVOY, LLC - WI 356      
920-537 2 Horicon WI   516J TON80 COMMUNICATIONS, LLC 356   2021-10-02   
920-537 4 Horicon WI   6529 T-MOBILE USA, INC. 356   2021-11-11   
920-537 5 Horicon WI   6529 T-MOBILE USA, INC. 356   2021-11-11   
920-537 6 Horicon WI   6529 T-MOBILE USA, INC. 356   2021-11-11   
920-537 7 Horicon WI   225C ONVOY, LLC - WI 356   2021-09-12   

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

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