A poorly designed urban solid waste collection system has an enormous impact on labour, operational and transport costs, and on society in general due to road contamination and negative effects on public health and the environment. This study proposes a methodology for designing an urban solid waste collection system. This methodology uses combinatorial optimisation and integer programing, and GIS tools to minimise collection time, and operational and transport costs while enhancing the current solid waste collection system. This methodology establishes feasible collection routes, determines an adequate vehicle fleet size and presents a comparative cost and sensitivity analysis of the results. The implementation of this methodology in a study case of a zone in Santiago yields significant cost savings in the total collection system.