Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Imperial MCA3, MO

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
636-461 A IMPRMO58RS2  9533 SOUTHWESTERN BELL 520      
636-461 0 IMPRMO58RS2  9533 SOUTHWESTERN BELL 520      
636-461 1 IMPRMO58RS2  9533 SOUTHWESTERN BELL 520      
636-461 2 IMPRMO58RS2  9533 SOUTHWESTERN BELL 520      
636-461 3 IMPRMO58RS2  9533 SOUTHWESTERN BELL 520   2007-07-20   
636-461 5 STLSMOGZEMD  145J TERRA NOVA TELECOM INC. 520   2024-02-13   
636-461 6   145J TERRA NOVA TELECOM INC. 520   2023-04-27   
636-461 7 STLSMOGZEMD  145J TERRA NOVA TELECOM INC. 520   2024-09-14   
636-461 8 STLSMO05XMX  624H ONVOY SPECTRUM, LLC 520   2024-03-23   
636-461 9 STLSMOGZLMD  490J BOOST SUBSCRIBERCO L.L.C. 520   2022-05-17   
636-464 A IMPRMO58RS2  9533 SOUTHWESTERN BELL 520      

Last updated: Sat, 04 Jul 2026 13:07:56 UTC

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