The stray load losses in electrical machines represent a non-negligible contribution of the total losses and are a key point for an accurate evaluation of the energy efficiency of the considered device. In this paper, a methodology using the 3-D finite element (FE) modeling approach and a posteriori loss calculation is presented for the estimation of the stray load losses. The case of a cage induction motor is investigated and results are compared with the experiment. The simulation is performed at different load conditions using a 3-D FE model with external circuit coupling.