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: 740

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
571-740 A Washington Zone 19 VA   138E ONVOY, LLC - VA 236   2025-12-06   
571-740 0 Washington Zone 19 VA   138E ONVOY, LLC - VA 236   2025-12-06   
571-740 1 Washington Zone 19 VA   138E ONVOY, LLC - VA 236   2025-12-08   

Last updated: Sat, 15 Nov 2025 03:38:44 UTC

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