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: 399

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-399 A Washington Zone 10 MD WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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