Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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OCN: 007J MEGAPHONE, INC.

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
857-357 A Cambridge MA CMBRMABEUMD  128      
857-357 1 Cambridge MA   128   2020-02-21   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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