In recent times, real-time simulation has been used to validate the testing and design of protection, control, and communications systems prior to their commissioning in the field, which has improved the reliability and security of the commissioning processes for electrical systems. This paper reviews the state-of-the-art and future trends in protection, control, and communications testing of electrical grids using real-time simulation. In addition, a summary is presented in which all the works and technologies mentioned are listed with the purpose of identifying new challenges in the proposed topic. Finally, future trends related to the use of real-time simulation for evaluating protection, control, and communications schemes are presented. Real-time simulation is very useful due to the increasing complexity of modern electrical power systems, therefore, it is necessary to use this kind of tool to facilitate field testing, avoid unnecessary work, and reduce costs for clients.