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: 437

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
425-437 A Maple Valley WA   6121 LEVEL 3 COMMUNICATIONS, LLC - WA 674      
425-437 0 Maple Valley WA   6121 LEVEL 3 COMMUNICATIONS, LLC - WA 674      
425-437 1 Maple Valley WA STTNWAHODSC  6121 LEVEL 3 COMMUNICATIONS, LLC - WA 674      
425-437 2 Maple Valley WA STTLWAWBDS1  483E ONVOY, LLC - WA 674   2020-10-11   
425-437 3 Maple Valley WA STTLWAWBDS1  483E ONVOY, LLC - WA 674   2020-10-11   
425-437 4 Maple Valley WA PLSBWAXXX0X  6010 NEW CINGULAR WIRELESS PCS, LLC 674   2025-01-12   
425-437 5 Maple Valley WA STTLWAWBXYZ  073H TELNYX LLC 674   2020-10-12   
425-437 6 Maple Valley WA STTLWAWBDSH  159F PEERLESS NETWORK OF WASHINGTON, LLC - WA 674   2023-09-30   
425-437 7 Maple Valley WA STTLWAWBDSH  159F PEERLESS NETWORK OF WASHINGTON, LLC - WA 674   2022-05-23   
425-437 8 Maple Valley WA STTLWAWBDSH  159F PEERLESS NETWORK OF WASHINGTON, LLC - WA 674   2021-03-28   

Last updated: Mon, 15 Sep 2025 02:24:40 UTC

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