Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Washington Zone 13, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-939 4 LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-939 5 LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-939 6 LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-939 7 LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-939 8   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-939 9   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-953 A LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-953 0 LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-953 1 LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-953 2 LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-953 3 LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-953 4 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2021-11-08   
301-953 5 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2021-11-08   
301-953 6 VINNVACBDS0  876D ONVOY, LLC - MD 236   2025-04-06   
301-953 7 LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-953 8 LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-953 9 LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-982 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-993 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      

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

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