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: 340

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
425-340 A Issaquah WA STTLWA060MD  6529 T-MOBILE USA, INC. 674      
425-340 0 Issaquah WA   6529 T-MOBILE USA, INC. 674   2022-02-05   
425-340 1 Issaquah WA   6529 T-MOBILE USA, INC. 674   2022-02-05   
425-340 2 Issaquah WA   6529 T-MOBILE USA, INC. 674   2022-02-05   
425-340 3 Issaquah WA   483E ONVOY, LLC - WA 674   2022-12-12   
425-340 4 Issaquah WA   6529 T-MOBILE USA, INC. 674   2022-07-29   
425-340 5 Issaquah WA   6529 T-MOBILE USA, INC. 674   2022-07-29   
425-340 6 Issaquah WA   6529 T-MOBILE USA, INC. 674   2022-07-29   
425-340 7 Issaquah WA   159F PEERLESS NETWORK OF WASHINGTON, LLC - WA 674   2021-12-05   
425-340 8 Issaquah WA   6529 T-MOBILE USA, INC. 674   2024-03-30   
425-340 9 Issaquah WA   6529 T-MOBILE USA, INC. 674   2021-12-04   

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

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