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.

NPA: 857 [Rate centres in NPA 857] [Dial plan for NPA 857]

NXX: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-257 A South Boston MA NRTNMAAACM4  5562 METROPCS, INC. 128      
857-257 0 South Boston MA NRTNMAAACM4  5562 METROPCS, INC. 128      
857-257 8 South Boston MA   892D ONVOY, LLC - MA 128   2024-03-07   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.