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

NXX: 994

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-994 A Newton MA   490J BOOST SUBSCRIBERCO L.L.C. 128   2025-07-03   
857-994 0 Newton MA   490J BOOST SUBSCRIBERCO L.L.C. 128   2025-07-03   
857-994 1 Newton MA   490J BOOST SUBSCRIBERCO L.L.C. 128   2025-10-23   

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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