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: 307

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
425-307 A Kirkland WA   6121 LEVEL 3 COMMUNICATIONS, LLC - WA 674      
425-307 0 Kirkland WA   073H TELNYX LLC 674   2020-12-11   
425-307 1 Kirkland WA   318J COMCAST IP PHONE, LLC 674   2010-08-27   
425-307 2 Kirkland WA   6121 LEVEL 3 COMMUNICATIONS, LLC - WA 674   2005-06-12   
425-307 3 Kirkland WA   6121 LEVEL 3 COMMUNICATIONS, LLC - WA 674      
425-307 4 Kirkland WA   483E ONVOY, LLC - WA 674   2020-10-11   
425-307 5 Kirkland WA   483E ONVOY, LLC - WA 674   2020-10-11   
425-307 6 Kirkland WA   6121 LEVEL 3 COMMUNICATIONS, LLC - WA 674      
425-307 7 Kirkland WA   495J STRATUS NETWORKS 674   2021-04-10   
425-307 8 Kirkland WA   508J CENTURYLINK COMMUNICATIONS, LLC 674   2021-08-30   
425-307 9 Kirkland WA   6121 LEVEL 3 COMMUNICATIONS, LLC - WA 674   2005-06-12   

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

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