Local Calling Guide

Area code/prefix search

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Washington Zone 13, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
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   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: Sun, 17 May 2026 03:26:51 UTC

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