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: 822

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-822 A Somerville MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   
857-822 6 Somerville MA CMBSMA01AMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2026-06-26   
857-822 7 Somerville MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   
857-822 8 Somerville MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   
857-822 9 Somerville MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.