Scientists are always working to increase the efficiency of solar cells in order to fulfill the rising need for energy sources. In these circumstances, Cs-based perovskites attracted attention due to their intriguing performance. In this paper, eight different Cs-halide perovskite absorbers (CsPbI3, CsPbBr3, CsSnI3, CsSnCl3, Cs2BiAgI6, Cs3Bi2I9, CsSn0.5Ge0.5I3, and Cs3Sb2I9) based solar cells are investigated using the SCAPS-1D simulator. Besides, ZnO and CFTS materials are proposed as promising candidates for charge transport material application, along with gold as the back contact. Initially, the impact of absorber and ETL thickness on photovoltaic performance was evaluated. Additionally, various parameters like thickness, donor and acceptor densities, and defect density are investigated to locate the final optimized Cs-based structures. From the optimization, it’s evident that among all optimizing features, absorbers, and HTL thickness, HTL acceptor density enhanced performance much more than other optimizing features. Furthermore, to evaluate the characteristics of these devices, series resistance, shunt resistance, working temperature, current-voltage density, and quantum efficiency are also simulated. Among all eight Cs-based perovskites, ITO/ZnO/CsPbBr3/CFTS/Au and ITO/ZnO/Cs3Bi2I9/CFTS/Au achieved the best performances with a conversion efficiency of 19.28% and 19.23%, respectively. Lastly, the SCAPS-1D simulator's performance is verified by using the wxAMPS simulator, with both yielding results that are in excellent agreement. In conclusion, this research provides useful information for optimizing solar cell architectures and understanding the effects of various device components.