There is continuous research on analytical, numerical, and (semi)empirical methods to predict wave-added resistance. Most of this research focuses on a particular area, like motion-induced wave added resistance, wave-added resistance in short waves, or is limited to head seas only. The practical application of most methods is therefore often limited. Moreover, most methods require detailed information on hull lines and results are rather sensitive to the discretization of those hull lines. Since 2006, MARIN has been investigating the feasibility of empirical methods that do not have those limitations. They only require the main particulars to predict wave-added resistance. Within the Sea Trial Analysis Joint Industry Project (STA-JIP), a method was developed for the correction of wave-added resistance in head seas covering both the motion-induced and the wave reflection-induced component. This method was further refined and extended to all wave directions within the service performance analysis JIP (SPA-JIP) in 2008. This article presents the results of the comparison between the prediction methods and model tests for almost 50 different ships, comprising more than 1500 tests in regular and irregular seas.