currently the cross-city route is operated as line s1 between heusweiler markt and sarreguemines, with services every 7.5 minutes during the day on the core section between siedlerheim and brebach station. originally, a five-minute interval service was planned for the central area, but this was rejected because it would have led to operational problems. on the sections using rail tracks between brebach and kleinblittersdorf and between heusweiler markt and siedlerheim there is a 15-minute interval service and on the kleinblittersdorf–sarreguemines section services operate every 30 minutes only in the morning and every 60 minutes at other times.