Abstract This paper proposes a model and implements a computational procedure to assess the reliability of electric power networks subjected to seismic load. A general electric network is first described and its functioning under ordinary conditions and under seismic action is analyzed. A reliability model to assemble small into larger components is proposed, which drastically simplifies the analysis. Power flow equations in the network are presented and modified to account for the current configuration of the network under seismic action. Seismic hazard is computed with the Cornell model. The whole procedure is applied to a real electric network and a simulation procedure is used to assess its reliability, measured via the probability distributions of suitable performance indexes.