Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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High Ridge MCA4, MO

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
636-671 A HGRGMO57RS2  9533 SOUTHWESTERN BELL 520      
636-671 0   9533 SOUTHWESTERN BELL 520      
636-671 1   9533 SOUTHWESTERN BELL 520      
636-671 2   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2010-12-17   
636-671 3   9533 SOUTHWESTERN BELL 520      
636-671 4   6529 T-MOBILE USA, INC. 520   2014-03-08   
636-671 5   093F ONVOY, LLC - MO 520   2002-11-19   
636-671 6   9533 SOUTHWESTERN BELL 520      
636-671 7   792K CHARTER IP ENABLED SERVICES, LLC 520   2008-08-21   
636-671 8   9533 SOUTHWESTERN BELL 520      
636-671 9   792K CHARTER IP ENABLED SERVICES, LLC 520   2005-10-31   
636-677 A HGRGMO56RS2  9533 SOUTHWESTERN BELL 520      

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

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