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: 747

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
571-747 A Manassas VA   138E ONVOY, LLC - VA 236   2026-02-01   
571-747 0 Manassas VA   138E ONVOY, LLC - VA 236   2026-02-01   
571-747 1 Manassas VA   138E ONVOY, LLC - VA 236   2026-02-06   
571-747 6 Manassas VA   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236   2026-04-27   
571-747 9 Manassas VA   138E ONVOY, LLC - VA 236   2026-03-22   

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

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