Reference DataRate Center DirectoryGRANDMOUND, IA Rate CenterGRANDMOUND — IAData last updated: October 30, 2026LATA634StateIAArea Codes1Exchanges (NXX)1Carriers1Coordinates41.8237890842089, -90.64820168977361Area Codes563Top CarriersCarrierOCNNXX CountGRAND MOUND COOP. TEL. ASSN.11911