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: 298

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-298 A Cambridge MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128      
857-298 0 Cambridge MA   624H ONVOY SPECTRUM, LLC 128   2017-11-20   
857-298 1 Cambridge MA   624H ONVOY SPECTRUM, LLC 128   2020-07-03   
857-298 2 Cambridge MA   624H ONVOY SPECTRUM, LLC 128   2020-06-05   
857-298 3 Cambridge MA   624H ONVOY SPECTRUM, LLC 128   2020-06-05   
857-298 4 Cambridge MA   624H ONVOY SPECTRUM, LLC 128   2020-06-05   
857-298 5 Cambridge MA   624H ONVOY SPECTRUM, LLC 128   2020-06-05   
857-298 6 Cambridge MA   624H ONVOY SPECTRUM, LLC 128   2020-07-03   
857-298 7 Cambridge MA   624H ONVOY SPECTRUM, LLC 128   2020-07-03   
857-298 8 Cambridge MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2019-10-01   
857-298 9 Cambridge MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2019-10-01   

Last updated: Sun, 04 Apr 2021 19:28:27 UTC

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.