Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: GRSMMO55RS2

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
636-451 A Gray Summit MCA5 MO 9533 SOUTHWESTERN BELL 520      
636-742 A Gray Summit MO 9533 SOUTHWESTERN BELL 520      

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

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