Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: CMBRMA01DS4

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
857-574 7 East Boston MA 7421 AT&T - LOCAL 128   2001-06-28   

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

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