Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 425 [Rate centres in NPA 425] [Dial plan for NPA 425]

NXX: 379

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
425-379 A Silver Lake WA SLLKWAXADS1  4324 ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 674      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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