Business process simulations (BPS) are considered a relevant and highly appli-cable method of analysis. BPS allow analysis of business processes under dif-ferent conditions. There are several approaches towards simulation of business processes such as discrete event simulations (DES), agent-based modelling and simulation (ABMS) or system dynamics (SD). This research focuses on ABMS approach towards simulation of business processes and its importance for sim-ulation of costs using time-driven activity-based costing (TDABC). Using ABMS approach, active elements of the system are represented by software agents which are programmed to follow some behavioral rules and autono-mously interact with each other. This is especially important for TADBC ap-proach to simulation of costs as simulation of resources has a direct impact on activity durations which drives the costs in TDABC approach. We present a case study, where is shown, how important is a process flow and organizational perspective for simulation of process costs using TDABC approach. The re-quired detail of business process simulation can be achieved through the use of ABMS approach. After that, we discuss other shortcomings of traditional busi-ness process simulation techniques which might have a significant impact on allocation of costs using TDABC and its simulations.