Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
571-400 A Washington Zone 8 VA 145J TERRA NOVA TELECOM INC. 236      
571-600 A Dulles Metro VA 145J TERRA NOVA TELECOM INC. 236      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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