Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

NXX: 491

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-491 A Hagerstown MD CMLDMDCM5MD  4720 USCOC OF CUMBERLAND, INC. DBA UNITED STATES CEL MD 240      

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

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