When new bus terminals are being planned or existing ones redesigned, suitable tools that are able to describe the complex situation at a terminal are needed. Using microsimulation, vehicle movements and interactions can be simulated and the congestion and capacity of a terminal can be evaluated. In this study, a discrete event simulation model is used in a case study of the Slussen bus terminal in Stockholm, Sweden. The model is calibrated and validated with empirical data that are automatically collected at the terminal. Already with this limited amount of data, the parameter time per boarding passenger can be calibrated with a relative error less than 1 % and the validation gives further insights into the data needed for calibration of a terminal simulation model.