Local Calling Guide

Area code/prefix search

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Washington Zone 4, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-531 9   829J PAETEC ITEL, LLC 236   2003-04-06   
301-546 A LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-546 0   9212 VERIZON MARYLAND, INC. 236   2014-06-06   
301-546 1   9212 VERIZON MARYLAND, INC. 236   2014-06-06   
301-546 2   9212 VERIZON MARYLAND, INC. 236   2014-06-06   
301-546 3   9212 VERIZON MARYLAND, INC. 236   2014-06-06   
301-546 4   9212 VERIZON MARYLAND, INC. 236   2014-06-06   
301-546 5   9212 VERIZON MARYLAND, INC. 236   2014-06-06   
301-546 6   9212 VERIZON MARYLAND, INC. 236   2014-06-06   
301-546 7   9212 VERIZON MARYLAND, INC. 236   2014-06-06   
301-546 8   9212 VERIZON MARYLAND, INC. 236   2014-06-06   
301-546 9   9212 VERIZON MARYLAND, INC. 236   2014-06-06   
301-559 A HYVLMDCMDS0  9212 VERIZON MARYLAND, INC. 236      
301-560 A   829J PAETEC ITEL, LLC 236   2025-04-02   
301-577 A LNHMMDLNDS0  9212 VERIZON MARYLAND, INC. 236      
301-583 A LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-583 0 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-583 1 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-583 2 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-583 3 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-583 4 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-583 5 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-583 6 BTVLMD12CMA  5562 METROPCS, INC. 236   2013-06-03   
301-583 7 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-583 8 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-583 9 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-618 A LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-618 0 SLSPMD91DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 236   2013-05-03   
301-618 1 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-618 2   829J PAETEC ITEL, LLC 236      
301-618 3   829J PAETEC ITEL, LLC 236      
301-618 4 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-618 5 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-618 6   829J PAETEC ITEL, LLC 236      
301-618 7 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-618 8 LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-618 9 WASLDCRGDS0  281E YMAX COMMUNICATIONS CORP. - MD 236   2008-10-10   
301-683 A WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-683 0 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-683 1 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-683 2 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-683 3 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-683 4 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2014-12-13   
301-683 5 VINNVACBDS0  876D ONVOY, LLC - MD 236   2014-10-24   
301-683 6 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-683 7   071F BANDWIDTH.COM CLEC, LLC - MD 236   2011-02-18   
301-683 8 WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2011-02-18   
301-683 9 WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2012-09-06   
301-699 A HYVLMDHYDS0  9212 VERIZON MARYLAND, INC. 236      
301-731 A LNHMMDLNDS0  9212 VERIZON MARYLAND, INC. 236      

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Last updated: Sat, 02 May 2026 12:20:53 UTC

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