A comparative study of group scheduling (GS) in a flow line cell is presented. Three simple scheduling heuristics are compared with two iterative improvement heuristics. The objective is minimizing makespan and total flow time separately. A number of modifications are proposed in order to explore the performance of the heuristics and to investigate the characteristics of the GS model. In addition, a timetabling procedure for multi-family cells is proposed, considering the presence of the zero processing times. Results showed that the proposed modification could improve the performance of the heuristics under study. The iterative improvement techniques were found appropriate for GS not only because of their superiority over the simple methods but because they can handle the phases’ interaction in GS as well. The tabu search heuristic is found preferable to the simulated annealing heuristic.