SummarySingle‐symbol generalized spatial modulation (GSM) improves upon the limitation of spatial modulation (SM) by reducing the number of required transmit antennas to achieve high data rates. In this paper, we investigate the application of media‐based modulation (MBM) based on radio frequency mirrors to single‐symbol GSM, with the aim of improving error performance. The theoretical average bit error probability of the proposed scheme is derived, employing a lower bound approach and used to validate the Monte Carlo simulation results. Finally, the effect of optimal and suboptimal mirror activation pattern selection employing Euclidean distance and channel amplitude coupled with antenna correlation is investigated for the proposed media‐based single‐symbol GSM system. The Monte Carlo simulation results obtained demonstrate a significant improvement over the conventional SM, GSM, and media‐based SM (MB‐SM) schemes in terms of error performance and spectral efficiency.