Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: BLTMMD915MD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
667-770 A Baltimore MD 691H AIRUS, INC. - MD 238      
667-770 1 Baltimore MD 691H AIRUS, INC. - MD 238   2015-09-21   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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