From 01 May-31 August 2025, seat reservations are compulsory for individual passengers travelling to the Jungfraujoch.
The reservation obligation applies for journeys from Grindelwald Terminal or Kleine Scheidegg to Jungfraujoch.
Further information:
https://www.jungfrau.ch/en-gb/jungfraujoch-top-of-europe/book-priority-boarding/
All information without guarantee.