Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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OCN: 0216 ARMSTRONG TEL. CO. OF MARYLAND

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
410-658 A Rising Sun MD RSSNMDXR0MD  238      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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