AbstractReduced-order models (ROMs) can provide computationally efficient approximations of the response of finite element models (FEMs). Recent studies have examined the explicit calibration of hysteretic, multi-degree-of-freedom ROMs utilizing FEM time-history response data, and have demonstrated how the calibrated ROM can adequately replace the original FEM for seismic risk assessment. This study considers the extension of this work for applications involving seismic protection devices (SPDs). The ROM is calibrated for the building structure without the device, and can be subsequently used to assess the performance for any desired SPD (no need to perform recalibration with the SPD). This is demonstrated considering three different SPD types: fluid viscous dampers, tuned-mass dampers, and inerter-based devices. It is verified that the calibration of the ROM without the protective device is sufficient, because existence of the SPD does not alter the fundamental hysteretic behavior of the building. The computational efficiency of the calibration process itself (performed only once) and of the resultant ROM can ultimately support a comprehensive design and assessment of the SPD-equipped structure considering nonlinear time-history analysis, circumventing traditional computational constraints that have incentivized the use of linear models in this context.