Hi SueC
On trains within Switzerland, seat reservations for most trains are not obligatory and are therefore not included in the train ticket. Seats may be reserved in trains which are marked “R” (reservation possible), “RE” (reservation recommended) or “RR” (reservation mandatory) under “comments” in the online timetable.
If a seat reservation is possible for the chosen stretch, it will be displayed under ticket options.
Kind regards
SandraI