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: 255

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
771-255 A Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-04-16   
771-255 0 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-04-16   
771-255 1 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-04-16   
771-255 2 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-04-16   
771-255 3 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-04-16   
771-255 4 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-04-16   
771-255 5 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-04-16   
771-255 6 Washington Zone 1 DC   515J IP HORIZON LLC 236   2026-04-16   
771-255 8 Washington Zone 1 DC   074F BANDWIDTH.COM CLEC, LLC - DC 236   2026-04-17   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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