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: 617

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-617 A Laurel MD LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      

Last updated: Tue, 07 Oct 2025 16:47:53 UTC

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