Local Calling Guide

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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-590 8 Washington Zone 10 MD GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-590 9 Washington Zone 10 MD GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-591 A Gaithersburg MD   829J PAETEC ITEL, LLC 236   2025-04-02   
301-591 0 Gaithersburg MD   829J PAETEC ITEL, LLC 236      
301-591 1 Gaithersburg MD   829J PAETEC ITEL, LLC 236      
301-591 2 Gaithersburg MD   829J PAETEC ITEL, LLC 236      
301-591 3 Gaithersburg MD   829J PAETEC ITEL, LLC 236      
301-591 4 Gaithersburg MD   829J PAETEC ITEL, LLC 236      
301-591 5 Gaithersburg MD   829J PAETEC ITEL, LLC 236      
301-591 6 Gaithersburg MD SLSPMD91DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 236   2020-04-19   
301-591 7 Gaithersburg MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2021-02-18   
301-591 8 Gaithersburg MD   829J PAETEC ITEL, LLC 236      
301-591 9 Gaithersburg MD   829J PAETEC ITEL, LLC 236      
301-592 A Washington Zone 3 MD SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      
301-592 0 Washington Zone 3 MD SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      
301-592 1 Washington Zone 3 MD SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      
301-592 2 Washington Zone 3 MD SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      
301-592 3 Washington Zone 3 MD SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      
301-592 4 Washington Zone 3 MD SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      
301-592 5 Washington Zone 3 MD SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      
301-592 6 Washington Zone 3 MD SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      
301-592 7 Washington Zone 3 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2003-07-29   
301-592 8 Washington Zone 3 MD SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      
301-592 9 Washington Zone 3 MD SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      
301-593 A Washington Zone 3 MD SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      
301-594 A Washington Zone 2 MD BTHSMDRPDS0  9212 VERIZON MARYLAND, INC. 236      
301-595 A Washington Zone 13 MD BTVLMDBVDS0  9212 VERIZON MARYLAND, INC. 236      
301-596 A Laurel (Baltimore LATA) MD CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
301-597 A Waldorf MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
301-597 0 Waldorf MD WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-03-11   
301-597 1 Waldorf MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2022-04-25   
301-597 2 Waldorf MD WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-03-21   
301-597 3 Waldorf MD WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-03-21   
301-597 4 Waldorf MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2022-04-25   
301-597 5 Waldorf MD WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-03-11   
301-597 6 Waldorf MD WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-03-11   
301-597 7 Waldorf MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2022-04-25   
301-597 8 Waldorf MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2022-03-10   
301-597 9 Waldorf MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2022-03-10   
301-598 A Washington Zone 12 MD SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-599 A Washington Zone 5 MD CLTNMDCLDS0  9212 VERIZON MARYLAND, INC. 236      
301-600 A Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-600 0 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240   2006-08-27   
301-600 1 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240   2006-08-27   
301-600 2 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240   2006-08-27   
301-600 3 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240   2006-08-27   
301-600 4 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240   2006-08-27   
301-600 5 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240   2006-08-27   
301-600 6 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240   2006-08-27   
301-600 7 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240   2006-08-27   

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Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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