Condensation trails, or contrails in short, are the white lines that can often be seen trailing high-altitude jet aircraft. Due to their interference with the local energy balance of the atmosphere they contribute to anthropogenic climate change. Research has shown strategies with great contrail mitigation potential at relatively small fuel and/or time cost in free flight. This thesis attempts to quantify contrail mitigation potential in practical and realistic scenario by introducing flight planning as tool for mitigation. A tool was developed that plans and simulates flights from the Netherlands to several destinations in North America. From the results it is clear that at least 50% of contrails can be mitigated at less than 2% additional fuel through flight planning. The results have confirmed the hypothesis that large shares of contrails can be mitigates against a few percent additional fuel consumption and flight time.