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: 924

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-924 A Mount Airy MD HGTWMDHGDMD  071F BANDWIDTH.COM CLEC, LLC - MD 240      
240-924 0 Mount Airy MD   071F BANDWIDTH.COM CLEC, LLC - MD 240   2022-04-15   
240-924 1 Mount Airy MD   071F BANDWIDTH.COM CLEC, LLC - MD 240   2022-04-15   
240-924 2 Mount Airy MD   876D ONVOY, LLC - MD 240   2023-08-10   
240-924 3 Mount Airy MD   876D ONVOY, LLC - MD 240   2023-08-10   
240-924 4 Mount Airy MD   876D ONVOY, LLC - MD 240   2023-08-10   
240-924 5 Mount Airy MD   876D ONVOY, LLC - MD 240   2023-08-10   
240-924 6 Mount Airy MD   876D ONVOY, LLC - MD 240   2023-08-10   
240-924 7 Mount Airy MD   876D ONVOY, LLC - MD 240   2024-04-05   
240-924 8 Mount Airy MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 240   2024-11-05   
240-924 9 Mount Airy MD   939H COMMIO, LLC 240   2022-11-17   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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