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
301-620 A Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-621 A Washington Zone 14 (Baltimore LATA) MD ODTNMDONDS0  9212 VERIZON MARYLAND, INC. 238      
301-622 A Washington Zone 3 MD SLSPMDCVDS0  9212 VERIZON MARYLAND, INC. 236      
301-623 A Washington Zone 13 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-623 0 Washington Zone 13 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-623 1 Washington Zone 13 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-623 2 Washington Zone 13 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-623 3 Washington Zone 13 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-623 4 Washington Zone 13 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-623 5 Washington Zone 13 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-623 6 Washington Zone 13 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-623 7 Washington Zone 13 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-623 8 Washington Zone 13 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-15   
301-623 9 Washington Zone 13 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-15   
301-624 A Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-624 0 Frederick MD FRDRMDFRKMD  5562 METROPCS, INC. 240   2019-08-30   
301-624 1 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-624 2 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-624 3 Frederick MD FRDRMDFRKMD  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240   2014-12-13   
301-624 4 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-624 5 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-624 6 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-624 7 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-624 8 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-624 9 Frederick MD FRDRMDFRKMD  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240   2014-12-13   
301-625 A Washington Zone 3 MD SLSPMDCVDS0  9212 VERIZON MARYLAND, INC. 236      
301-626 A Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-627 A Washington Zone 15 MD MRBOMDMBDS0  9212 VERIZON MARYLAND, INC. 236      
301-628 A Washington Zone 3 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-628 0 Washington Zone 3 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-628 1 Washington Zone 3 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-628 2 Washington Zone 3 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-628 3 Washington Zone 3 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-628 4 Washington Zone 3 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-628 5 Washington Zone 3 MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-628 6 Washington Zone 3 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-11-21   
301-628 7 Washington Zone 3 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-11-21   
301-628 8 Washington Zone 3 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-11-21   
301-628 9 Washington Zone 3 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2011-08-19   
301-629 A Washington Zone 14 (Baltimore LATA) MD CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
301-629 0 Washington Zone 14 (Baltimore LATA) MD CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
301-629 1 Washington Zone 14 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-24   
301-629 2 Washington Zone 14 (Baltimore LATA) MD CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
301-629 3 Washington Zone 14 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-24   
301-629 4 Washington Zone 14 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-24   
301-629 5 Washington Zone 14 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-24   
301-629 6 Washington Zone 14 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
301-629 7 Washington Zone 14 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
301-629 8 Washington Zone 14 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-24   
301-629 9 Washington Zone 14 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   

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

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