Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

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   9533 SOUTHWESTERN BELL 520      
636-461 1   9533 SOUTHWESTERN BELL 520      
636-461 2   9533 SOUTHWESTERN BELL 520      
636-461 3   9533 SOUTHWESTERN BELL 520   2007-07-20   
636-461 5   145J TERRA NOVA TELECOM INC. 520   2024-02-13   
636-461 6   145J TERRA NOVA TELECOM INC. 520   2023-04-27   
636-461 7   145J TERRA NOVA TELECOM INC. 520   2024-09-14   
636-461 8   624H ONVOY SPECTRUM, LLC 520   2024-03-23   
636-461 9   490J DISH WIRELESS, LLC 520   2022-05-17   
636-464 A IMPRMO58RS2  9533 SOUTHWESTERN BELL 520      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.