Local Calling Guide

Area code/prefix search

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Old Monroe, MO

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
636-665 A OLMRMOXARS1  9787 BRIGHTSPEED OF MISSOURI, LLC 520      
636-665 0 STLSMOWQ8MD  073H TELNYX LLC 520   2020-08-07   
636-665 5 OLMRMOXARS1  9787 BRIGHTSPEED OF MISSOURI, LLC 520      
636-665 6   145J TERRA NOVA TELECOM INC. 520   2026-01-04   

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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