Bodensee S-Bahn is an international marketing effort grouping various regional rail services (S-Bahn, R/RB, RE, RE/REX) around Lake Constance (German: Bodensee) in Austria, Germany and Switzerland.

Cross-border rail and bus services along with Lake Constance ferries (Friedrichshafen–Romanshorn, Konstanz–Meersburg) can be used with the Bodensee Ticket.

[1] With a few exceptions, most services marketed as part of the Bodensee S-Bahn belong to other S-Bahn networks.

Services use the railway lines of the Lake Constance Belt Railway (Bodenseegürtelbahn) and connecting lines.

As of April 2024[update], the following services are part of Bodensee S-Bahn (railway stations in bold are included in the Bodensee-S-Bahn network, others are not):[2]