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: 540

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-540 A Washington Zone 13 (Baltimore LATA) MD   507J THE VOICE APPLICATION NETWORK, LLC 238   2025-04-26   
240-540 0 Washington Zone 13 (Baltimore LATA) MD BLTMMDCHX7X  073H TELNYX LLC 238   2019-09-27   
240-540 1 Washington Zone 13 (Baltimore LATA) MD   507J THE VOICE APPLICATION NETWORK, LLC 238   2016-11-26   
240-540 3 Washington Zone 13 (Baltimore LATA) MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2020-03-18   
240-540 4 Washington Zone 13 (Baltimore LATA) MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2020-04-30   
240-540 5 Washington Zone 13 (Baltimore LATA) MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2020-04-30   
240-540 6 Washington Zone 13 (Baltimore LATA) MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-03-04   
240-540 7 Washington Zone 13 (Baltimore LATA) MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2020-06-11   
240-540 8 Washington Zone 13 (Baltimore LATA) MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2020-06-11   
240-540 9 Washington Zone 13 (Baltimore LATA) MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2020-06-11   

Last updated: Fri, 10 Jul 2026 02:55:48 UTC

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