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: 788

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
509-788 A Prosser WA PRSRWAXARS0  4521 UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - WA 676      
509-788 0 Prosser WA   4521 UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - WA 676      
509-788 1 Prosser WA   4521 UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - WA 676      
509-788 2 Prosser WA   483E ONVOY, LLC - WA 676   2021-06-27   
509-788 3 Prosser WA   145J TERRA NOVA TELECOM INC. 676   2025-07-19   
509-788 5 Prosser WA   6010 NEW CINGULAR WIRELESS PCS, LLC 676   2006-01-05   
509-788 7 Prosser WA   483E ONVOY, LLC - WA 676   2021-11-13   
509-788 8 Prosser WA   5812 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WA 676   2016-03-24   

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

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