Poor urban planning and traffic congestion lead to excessive delays in workers' transit times and decrease their quality of life, especially in emerging countries.Several medium and large companies have a need to hire a transport service for their staff.In this type of transportation system, there is a heterogeneous fleet of vehicles, which are assigned to a set of pre-defined routes.However, the total transport delay can be even greater if the private transportation system is inefficient or not controlled.The approach proposed in this study seeks to optimize the private transport service by defining the best allocation of its fleet to its routes.A mathematical model is proposed to minimize user wait times.This approach is validated using real data obtained from a transport company in Colombia.The results demonstrate the quantitative benefits that can be achieved when the proposed approach is implemented, represented by a considerable reduction in user wait times.