Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 227 [Rate centres in NPA 227] [Dial plan for NPA 227]

NXX: 310

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
227-310 A Washington Zone 10 MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
227-310 0 Washington Zone 10 MD   876D ONVOY, LLC - MD 236   2026-09-17   
227-310 1 Washington Zone 10 MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-09-28   
227-310 2 Washington Zone 10 MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-09-28   
227-310 3 Washington Zone 10 MD CHCHMDBEWMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-04-27   
227-310 4 Washington Zone 10 MD CHCHMDBEWMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-04-27   
227-310 5 Washington Zone 10 MD CHCHMDBEWMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-04-27   
227-310 6 Washington Zone 10 MD CHCHMDBEWMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-04-27   
227-310 7 Washington Zone 10 MD CHCHMDBEWMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-04-27   
227-310 8 Washington Zone 10 MD CHCHMDBEWMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-04-27   

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

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