Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: BLTOMDXIDS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
443-320 A Baltimore MD 6050 GLOBAL CROSSING LOCAL SERVICES, INC. - MD 238      
443-320 0 Baltimore MD 6050 GLOBAL CROSSING LOCAL SERVICES, INC. - MD 238      

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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