Abstract: This study considers a specific case of flowshop problems in which some jobs might not visit all the production stages. To tackle the problem, a hybrid metaheuristic which is a combination of electromagnetic algorithm and simulated annealing, called EMSA is presented. The optimization criterion is makespan. To evaluate the proposed hybrid metaheuristic, the study carries out a benchmark by which EMSA is compared against some dispatching rules as well as pure simulated annealing and electromagnetic algorithms in a fixed given computational time. All the results and analysis, obtained through the benchmark, show that EMSA is an effective algorithm for the problem.