In this paper we present an evolutionary approach to the joint management of inventory and routing in a retail chain. With this purpose, an ad-hoc evolutionary algorithm was designed which includes a non-standard individual representation and two mutation operators specific to this particular problem. Also, this work considers the inclusion of time-window constraints in the problem. We compare this approach to that of previous work, in which two levels were used: one for obtaining the delivery patterns that minimise the inventory costs and another to find the optimal routes in order to minimise transportation costs. The analysis performed allows us to conclude that the one-level approach obtains better results than the previously used two-level methodology in a shorter time.