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: 323

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-323 A Laurel MD LARLMDCC5MD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-323 0 Laurel MD   7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-323 1 Laurel MD   7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-323 2 Laurel MD   7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-323 3 Laurel MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2010-03-07   
301-323 4 Laurel MD   7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-323 5 Laurel MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2010-03-07   
301-323 6 Laurel MD   7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-323 7 Laurel MD   7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-323 8 Laurel MD   071F BANDWIDTH.COM CLEC, LLC - MD 236   2010-02-22   
301-323 9 Laurel MD   7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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