Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 571 [Rate centres in NPA 571] [Dial plan for NPA 571]

NXX: 736

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
571-736 A Washington Zone 17 VA   138E ONVOY, LLC - VA 236   2025-10-26   
571-736 0 Washington Zone 17 VA   138E ONVOY, LLC - VA 236   2025-10-26   
571-736 1 Washington Zone 17 VA   138E ONVOY, LLC - VA 236   2025-10-26   

Last updated: Mon, 15 Sep 2025 02:24:40 UTC

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