Local Calling Guide

Area code/prefix search

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

NXX: 931

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-931 A Boston MA CMBRMABE02T  9102 VERIZON NEW ENGLAND INC. 128      

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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