Tickets versus passes
Point to point train tickets can be purchased online, and through the staffed desk or ticketing machines at rail stations in Switzerland. In most cases people traveling in Switzerland are better off with some kind of rail pass. If you have a rail pass that includes free traveling, you don’t need a ticket at all. If you have a Swiss Half Fare Card, you only pay 50% of the ticket price.
Domestic tickets for Switzerland do not need to be booked in advance. You can do so to save some time, but it's not required. Seat reservations do need to be purchased in advance, but these are mostly not required.
Booking tickets early does not get you a lower fare. A few exceptions apply, like resellers which may offer promotions on their rail products.
Find ticket prices and points of sale.
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