This chapter presents the geometric modeling of the parts for which manufacturing cost estimates is to be carried out, and then the SolidWorks automatic manufacturing Cost Estimation tool is discussed so that users can use it for carrying out the costing task for their product during the design stage. Manufacturing cost is one of the main factors in machine design process in order to choose the most suitable solution; therefore, accurate estimation in the early design phases is fundamental. Design to cost implies to manage a vast amount of manufacturing knowledge that has to be linked to the design parameters. Feature-based three-dimensional (3D) computer-aided design (CAD) models contain data that are useful for cost estimation, but, despite the numerous works on features recognition and extraction, no cost estimation software system yet assures reliable results. SolidWorks 3D CAD software has a tool for rapid manufacturing cost estimation where design features are automatically linked to manufacturing operations.