Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 771 [Rate centres in NPA 771] [Dial plan for NPA 771]

NXX: 256

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
771-256 A Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-11-21   
771-256 0 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-11-21   
771-256 1 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-11-21   
771-256 2 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-11-21   
771-256 3 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-11-21   
771-256 4 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-11-21   
771-256 6 Washington Zone 1 DC   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236   2026-11-23   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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