Local Calling Guide

Area code/prefix search

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Gray Summit MCA5, MO

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
636-451 A GRSMMO55RS2  9533 SOUTHWESTERN BELL 520      
636-451 0 GRSMMO55RS2  9533 SOUTHWESTERN BELL 520      
636-451 1 GRSMMO55RS2  9533 SOUTHWESTERN BELL 520      
636-451 2 GRSMMO55RS2  9533 SOUTHWESTERN BELL 520      
636-451 3 STLSMOGZEMD  145J TERRA NOVA TELECOM INC. 520   2024-04-21   
636-451 4 GRSMMO55RS2  9533 SOUTHWESTERN BELL 520      
636-451 5 GRSMMO55RS2  9533 SOUTHWESTERN BELL 520      
636-451 6   792K CHARTER IP ENABLED SERVICES, LLC 520   2005-09-02   
636-451 7 STLSMOPLDS4  4932 LEVEL 3 COMMUNICATIONS, LLC - MO 520   2005-12-16   
636-451 8 STLSMOWQDS2  093F ONVOY, LLC - MO 520   2024-03-02   
636-451 9 STLSMOPLDS4  4932 LEVEL 3 COMMUNICATIONS, LLC - MO 520   2004-12-15   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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