Traditional force-based and displacement-based methods for the design of seismic isolation systems uses simplifying assumptions to account for the nonlinear behavior of seismic isolators. This results in inaccurate predictions of the structures response during earthquakes. As an alternative to overcome the limitations of traditional methods, energy can be set as the main criterion in the design of seismic isolators. In this study, an energy-based design method is applied to a seismic isolation system to include the nonlinear behavior of seismic isolators; thus, simplified assumptions to predict the force-displacement demand on the structure are avoided. This method is applied to a four-span highway bridge with seismic isolators atop the three columns and at the abutments. A set of nonlinear structural analyses is performed through computer software to assess the abilities of the traditional versus energy-based design methods to accurately predict the response of the structure during earthquakes. Based on the analyzed cases, the proposed energy-based design method resulted with more accurate predictions in force and displacement demands than traditional methods did. The proposed method also effectively confines all plastic deformations into the seismic isolators while the columns and deck remain elastic and undamaged.