Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 507 [Rate centres in NPA 507] [Dial plan for NPA 507]

NXX: 231

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
507-231 A Janesville MN   184D ONVOY, LLC - MN 620      
507-231 7 Janesville MN   184D ONVOY, LLC - MN 620      

Last updated: Sun, 17 May 2026 03:26:51 UTC

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