Local Calling Guide

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Search area code/prefix (NPA/NXX)
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NPA: 240 [Rate centres in NPA 240] [Dial plan for NPA 240]

NXX: 553

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-553 A Washington Zone 13 MD WASHDCRKDS3  8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-553 0 Washington Zone 13 MD WASHDCRKDS3  8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-553 1 Washington Zone 13 MD WASHDCRKDS3  8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-553 2 Washington Zone 13 MD WASHDCSWFMD  2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
240-553 3 Washington Zone 13 MD WASHDCRKDS3  8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-553 4 Washington Zone 13 MD BTVLMD127MD  5562 METROPCS, INC. 236   2018-06-18   
240-553 7 Washington Zone 13 MD ARTNVAARXDY  318J COMCAST IP PHONE LLC 236   2013-09-05   
240-553 8 Washington Zone 13 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2011-04-23   
240-553 9 Washington Zone 13 MD WASHDCRKDS3  8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      

Last updated: Wed, 01 Jun 2022 03:09:23 UTC

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