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.

OCN: 156J RCLEC, INC.

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
251-385 A Mobile AL MOBLALAZ03Z  480      
312-858 A Chicago Zone 01-Calumet IL CHCGILDTDMD  358      
612-503 A Twin Cities MN MPLSMNDTX8Y  628      
857-895 A Boston MA CMBRMABE8MD  128      

Last updated: Sun, 17 May 2026 03:26:51 UTC

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