Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 620 [Rate centres in NPA 620] [Dial plan for NPA 620]

NXX: 558

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
620-558 A Riverton KS WCHTKSBRY0X  425J CSC WIRELESS, LLC 532      
620-558 0 Riverton KS WCHTKSBRY0X  425J CSC WIRELESS, LLC 532   2021-12-05   
620-558 1 Riverton KS WCHTKSTPOMD  939H COMMIO, LLC 532   2024-02-25   
620-558 5 Riverton KS   145J TERRA NOVA TELECOM INC. 532   2025-05-28   
620-558 8 Riverton KS WCHTKSBRXPZ  624H ONVOY SPECTRUM, LLC 532   2024-04-07   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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