In the last few years, there has been extensive research in the design and fabrication of tandem solar cells. To analyse the transport in these devices and to optimize the device structure for enhanced response, simulation of these device configurations are crucial. In our work, we simulate the optoelectronic behaviour of a perovskite-silicon multi-junction tandem solar cell with a silicon tunnel junction, by accounting for different optical losses at the interface of each layer and by taking into account the limits of different recombination mechanisms (radiative and non-radiative). We have used a simple TCAD-based approach to understand and model the different transport mechanisms and losses in a perovskite-silicon tandem solar cell. We have compared simulated characteristics with corresponding measured characteristics from an experimental device. © 2020 IEEE.