This paper analyzes the importance of costs and unit rates for airlines. Increasing competition based on the growing trends in aviation industry requires airline companies to act as both revenue- and cost-oriented to gain competitive advantage. "En route charges" is one of the direct operational cost items of airlines. In this study, Eurocontrol En Route Charging System was handled. Six Eurocontrol Member States applying different cost calculation methods were selected and compared in terms of national costs, chargeable costs to users, number of service units and unit rates in 2011 and 2013. For airlines, low unit rates are factors which can be reflected to ticket prices. In this respect, choosing a route with lower unit rates in comparison to their rivals might enable them to reduce the costs and to improve their competitiveness.