Abstract Codesharing is a widespread practice that allows an airline to put one of its flight numbers on a flight operated by a partner airline and consider it in its own network. Even though it has been repeatedly demonstrated that this type of partnership can generate important additional revenue, it is increasingly complex for an airline to choose which flights to codeshare with which partners. We propose two heuristic methods that maximize the revenue of an airline over a selection of potential codeshare flights considering two aspects that were not fully considered in the literature: the impact of adding a codeshare flight in the network and the interactions that exist between flights that are chosen as codeshare. These methods were used to optimize the codeshare flight selection of Air Canada. In comparison with two methods currently used in the airline industry, the developed algorithms propose codeshare flight selections that generate greater revenue.