Abstract | Several possibilities are examined for the simplified nonlinear dynamic analysis of a typical cantilevered-deck three-span bridge (75+120+75m) of Egnatia Odos as a practical tool for estimating seismic behavior. The options presently available to a designer are actually restricted to the static pushover analysis and the full nonlinear dynamic analysis. While the first is often inaccurate for asymmetric structures, the second is usually avoided due to complexity. As an intermediate solution, equivalent oscillators are tested using nonlinear dynamic analysis and having simple or complex, coupled or uncoupled forcedeformation relationships in each direction. Additionally, the roles of the simultaneous excitation in the two horizontal directions and of the horizontal curvature of the deck are examined. Using as reference the full model of the bridge with concurrent excitation in both directions, we estimate the error in omitting any of the above factors. In summary, we calibrate a series of simplifications that can be used by engineers to achieve a simple yet accurate analysis of cantilevered-deck bridges.