Recent advances in nanofabrication techniques allow for the manufacture of optical metamaterials, bringing their unique and extraordinary properties to the visible regime and beyond. However, an analytical description of optical nanoplasmonic metamaterials is challenging due to the characteristic optical behavior of metals. Here we present an analytical theory that allows us to bring established microwave metamaterials models to optical wavelengths. This method is implemented for nanoscaled plasmonic wire-mesh and trihelical metamaterials, and we obtain an accurate prediction for their dispersive behavior at optical and near-IR wavelengths.