Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Gaithersburg, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-977 A GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-987 A GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-990 A GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      

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Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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