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: 366

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
509-366 A Kennewick WA KNWCWABB1MD  6270 UNITED STATES CELLULAR - WA 676      
509-366 0 Kennewick WA   6270 UNITED STATES CELLULAR - WA 676      
509-366 1 Kennewick WA   6270 UNITED STATES CELLULAR - WA 676      
509-366 2 Kennewick WA   6270 UNITED STATES CELLULAR - WA 676      
509-366 3 Kennewick WA   6270 UNITED STATES CELLULAR - WA 676      
509-366 4 Kennewick WA   6270 UNITED STATES CELLULAR - WA 676      
509-366 5 Kennewick WA   6270 UNITED STATES CELLULAR - WA 676      
509-366 6 Kennewick WA   6270 UNITED STATES CELLULAR - WA 676      
509-366 7 Kennewick WA   6270 UNITED STATES CELLULAR - WA 676      
509-366 8 Kennewick WA   6270 UNITED STATES CELLULAR - WA 676      
509-366 9 Kennewick WA   6270 UNITED STATES CELLULAR - WA 676      

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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