Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 509 [Rate centres in NPA 509] [Dial plan for NPA 509]

NXX: 231

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
509-231 A Kennewick WA KNWCWAXAX3X  483E ONVOY, LLC - WA 676      
509-231 0 Kennewick WA   624H ONVOY SPECTRUM, LLC 676   2024-06-18   
509-231 1 Kennewick WA   490J DISH WIRELESS, LLC 676   2023-06-06   
509-231 2 Kennewick WA   939H COMMIO, LLC 676   2024-04-18   
509-231 3 Kennewick WA   5812 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WA 676   2023-04-17   
509-231 4 Kennewick WA   5812 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WA 676   2023-06-19   
509-231 5 Kennewick WA   483E ONVOY, LLC - WA 676   2023-06-05   
509-231 6 Kennewick WA   6010 NEW CINGULAR WIRELESS PCS, LLC 676   2023-04-07   
509-231 7 Kennewick WA   483E ONVOY, LLC - WA 676   2023-03-19   
509-231 8 Kennewick WA   483E ONVOY, LLC - WA 676   2023-01-12   
509-231 9 Kennewick WA   6529 T-MOBILE USA, INC. 676   2022-11-12   

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

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