Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: MDRVCAXFRS3

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
707-574 A Mad River CA 4420 FRONTIER CALIFORNIA INC. 722      
707-574 6 Mad River CA 4420 FRONTIER CALIFORNIA INC. 722      

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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