Local Calling Guide

Area code/prefix search

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

NXX: 742

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-742 A Washington Zone 14 (Baltimore LATA) MD BLTMMDCHXKX  478J NUSO, LLC 238      
240-742 0 Washington Zone 14 (Baltimore LATA) MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2023-10-20   
240-742 1 Washington Zone 14 (Baltimore LATA) MD BLTMMDCHXKX  478J NUSO, LLC 238   2021-01-21   
240-742 2 Washington Zone 14 (Baltimore LATA) MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-03-04   
240-742 3 Washington Zone 14 (Baltimore LATA) MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-07-12   
240-742 4 Washington Zone 14 (Baltimore LATA) MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2022-10-16   
240-742 5 Washington Zone 14 (Baltimore LATA) MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2022-03-03   
240-742 6 Washington Zone 14 (Baltimore LATA) MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-05-23   
240-742 7 Washington Zone 14 (Baltimore LATA) MD BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238   2024-12-23   
240-742 8 Washington Zone 14 (Baltimore LATA) MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2022-03-03   
240-742 9 Washington Zone 14 (Baltimore LATA) MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2021-12-02   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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