In reply to Cellinski:
> No, fares stay at the same price.
This was the case but it has changed in about the last year. You can save a *lot* (up to 50% in some cases) with the new advance fares booked online and printed at home (note you MUST print it or it is not valid, showing it on a mobile device is not acceptable and there is a CHF100 = about £75 fine for not having a valid ticket, you MUST carry your Passport or EU/EEA/EFTA ID card when travelling, no other identification is accepted, and the tickets are train specific, are not changeable/refundable and have no validity if you miss your train for whatever reason), though they have a mobile app on which you can also buy and show on your phone (but again note you MUST be able to show it, "battery run out" is not accepted as an excuse).
I would therefore recommend advance booking and printing at home if you can commit to specified trains.
Post edited at 13:47