This paper presents an efficiency analysis of five single-phase transformer-less inverters for photovoltaic applications (Full H-Bridge, Half H-Bridge, H5, HERIC and NPC inverters) implemented with different topologies of switches. Silicon (Si) and Silicon Carbide (SiC) diodes have been considered combined with two kinds of IGBTs. Simulation results have been obtained for each of the systems in different operating conditions by using PLECS software. Power losses and European Efficiency (EE) have been calculated for all the topologies by including the real characteristics of the switches in the thermal models provided by the software.