Demand for air traffic is growing worldwide. In order to accommodate this growth, existing infrastructure such as gates should be used more efficiently. One technique to increase gate utilization is by introducing gate pit-stops. Introducing gate pit-stops leads to additional towing movements which can potentially interfere with other traffic on the apron. This in turn will lead to delays, which is undesirable. Currently, gate pit-stops are only performed for flights with a turnaround time of three hours or more. In order to investigate whether pit-stops can be effectively introduced on a broader scale, a model has been created that simulates gate assignments and apron movements. This model provides insight in the effect of gate pit-stops on gate utilization and apron congestion for different airport scenarios. Results show that introducing pit-stops for flights with a turnaround time of less than 180 minutes leads to an increase in flights that can be handled at a gate instead of a remote stand, at a small delay penalty. Airlines and airports can benefit from these findings as they will be able to handle more flights at a gate using existing infrastructure.