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 HGRGMO57RS2  9533 SOUTHWESTERN BELL 520      
636-671 1 HGRGMO57RS2  9533 SOUTHWESTERN BELL 520      
636-671 2 MNCHMOAQGT1  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2010-12-17   
636-671 3 HGRGMO57RS2  9533 SOUTHWESTERN BELL 520      
636-671 4 STLVMOOH6MD  6529 T-MOBILE USA, INC. 520   2014-03-08   
636-671 5 STLSMOWQDS2  093F ONVOY, LLC - MO 520   2002-11-19   
636-671 6 HGRGMO57RS2  9533 SOUTHWESTERN BELL 520      
636-671 7   792K CHARTER IP ENABLED SERVICES, LLC 520   2008-08-21   
636-671 8 HGRGMO57RS2  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: Sun, 01 Jun 2025 02:18:11 UTC

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