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.

Switch: CMBRMABETMD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
857-279 6 Newton MA 321J HD CARRIER LLC 128   2016-09-03   
857-358 5 Quincy MA 321J HD CARRIER LLC 128   2020-05-24   
857-557 A Boston MA 321J HD CARRIER LLC 128      
857-557 9 Boston MA 321J HD CARRIER LLC 128   2019-10-18   

Last updated: Sat, 15 Nov 2025 03:38:44 UTC

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