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   
571-740 4 Washington Zone 19 VA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-02-14   
571-740 5 Washington Zone 19 VA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-02-14   
571-740 6 Washington Zone 19 VA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-02-14   
571-740 7 Washington Zone 19 VA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-02-14   
571-740 8 Washington Zone 19 VA   138E ONVOY, LLC - VA 236   2026-01-11   
571-740 9 Washington Zone 19 VA   138E ONVOY, LLC - VA 236   2026-01-11   

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

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