Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 206 [Rate centres in NPA 206] [Dial plan for NPA 206]

NXX: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
206-257 A Seattle WA STTLWA03X1X  318J COMCAST IP PHONE, LLC 674      
206-257 0 Seattle WA STTLWA03X1X  318J COMCAST IP PHONE, LLC 674   2005-02-26   
206-257 1 Seattle WA STTLWA03X1X  318J COMCAST IP PHONE, LLC 674   2010-09-28   
206-257 2 Seattle WA STTNWAHODSC  6121 LEVEL 3 COMMUNICATIONS, LLC - WA 674   2010-05-10   
206-257 3 Seattle WA STTNWAHODSC  6121 LEVEL 3 COMMUNICATIONS, LLC - WA 674   2010-05-10   
206-257 4 Seattle WA STTLWA03X1X  318J COMCAST IP PHONE, LLC 674   2010-05-10   
206-257 5 Seattle WA STTLWA03X1X  318J COMCAST IP PHONE, LLC 674   2010-07-30   
206-257 6 Seattle WA TKWLWAZSPS0  7173 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 674   2005-02-28   
206-257 7 Seattle WA STTLWAWBDS1  483E ONVOY, LLC - WA 674   2010-06-14   
206-257 8 Seattle WA PLSBWAXXX0X  6010 NEW CINGULAR WIRELESS PCS, LLC 674   2005-03-22   
206-257 9 Seattle WA PLSBWAXXX0X  6010 NEW CINGULAR WIRELESS PCS, LLC 674   2005-03-22   

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

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