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.
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Switch: RCFRILRCXEX

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
779-330 A Belvidere IL 478J NUSO, LLC 360      
779-330 1 Belvidere IL 478J NUSO, LLC 360   2021-08-21   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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