Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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OCN: 4773 XO MARYLAND, LLC

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
443-578 A Cockeysville MD BLTMMDSNDS5  238      
443-578 0 Cockeysville MD   238      
443-578 4 Cockeysville MD   238      
443-578 5 Cockeysville MD   238      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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