Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Union MCA5, MO

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
636-744 A UNINMOLURS0  9533 SOUTHWESTERN BELL 520      
636-744 0 UNINMOLURS0  9533 SOUTHWESTERN BELL 520   2006-04-27   
636-744 1 OLVEMOAX0MD  792K CHARTER IP ENABLED SERVICES, LLC 520   2006-07-20   
636-744 2 NWTPMOABGT1  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2007-12-05   
636-744 3 NWTPMOABGT1  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2007-12-05   
636-744 4 NWTPMOABGT1  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2007-12-05   
636-744 5 NWTPMOABGT1  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2008-05-01   
636-744 6 NWTPMOABGT1  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2008-07-01   
636-744 7 STLSMO05XMX  624H ONVOY SPECTRUM, LLC 520   2025-01-11   
636-744 8 OLVEMOAX0MD  792K CHARTER IP ENABLED SERVICES, LLC 520   2013-04-21   
636-744 9 STLVMOOH6MD  6529 T-MOBILE USA, INC. 520   2006-09-05   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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