Jun 29, 2014 - 10:23 AM
In this case, the Swiss Transfer Ticket is not the best option for two reasons:
- It only allows traveling via the quickest or shortest route, which does not include the Golden Pass line in your case. See the Swiss Transfer Ticket page for more information;
- As you said, the last leg of your trip to the Jungfraujoch is not included. Also, you will not get a discount on this pretty expensive additional ticket.
You're better off getting a Swiss Half Fare Card, which gives you 50% off the entire journey, and allows you to pick any route you want. See here for how it works, prices, etc.
One more thing: you said "starting in the evening to catch my train from Interlaken Ost and reach Geneva by next morning". Be sure to study the timetable, as there are no overnight trains in Switzerland. You'd better book accommodation along the way. There are affordable ones in Interlaken and Grindelwald, for example.
Also it would be good to have an alternative travel plan, because going up to the Jungfraujoch is only worth the time and money if it isn't covered in clouds.