Buying train ticket in advance vs. day of-Zurich to Bellizona

There is no advantage in buying tickets for Swiss trains in advance.

• There is no discount for advance purchase, the price is always the same.
• There are no reservations needed or usually possible, tickets cannot "sell out".
• Tickets are valid for any train on the date shown on the ticket, and of course there is at least one train per hour on all Swiss train routes. So just buy a ticket and get on the next train.

Just buy on the day at the station using either the ticket machine or manned ticket desk.

The one exception is the supersaver tickets which are available for less popular trains.

BUT, you say you are flying in, so surely you want tickets from Zürich airport station (Zürich Flughafen) to Bellinzona, NOT from Zürich HB.

NOTE: Customs doesn't take any time. It is immigration (passport control) which can take time, but Zürich airport is very fast

While normally not necessary, I see that many afternoon trains, especially after 3:30 pm are shown as "high occupancy expected" (its start of the weekend). You can buy seat reservations for 5 CHF per seat at:
https://www.sbb.ch/ticketshop/b2c/adw.do?sprache=en&artikelnummer=1993

You could buy reservations for multiple departures if you are worried. You don't have to actually buy the tickets until you arrive at the airport train station and you know for sure which train you can take.

Thank you, this is very helpful. I also saw that "very high occupancy" icon and didn't want to be stranded in Zurich since we have hotel reservations in Locarno. Another question: I see that there is not an option to purchase train tickets on Sunday morning, 8/27 from Locarno to Venice on Rick Steves website. I hope that's not due to a lack of availability. These rail websites are a bit confusing, so if you have a suggestion on the most user-friendly site for train travel in Italy, please share. And thanks again!

I see that there is not an option to purchase train tickets on Sunday morning, 8/27 from Locarno to Venice on Rick Steves website.

By this I assume you are using the Raileurope click-through link on the Rick Steves website. NEVER buy tickets from Raileurope (except in an emergency) because Raileurope is a reseller and they only show trains they can charge a mark-up on.

www.sbb.ch/en will sell you tickets, but you might get a better deal by buying tickets from Bellinzona to Venezia S. Lucia at http://www.trenitalia.com/tcom-en, which would be an advance purchase non-refundable ticket and they include seat reservations with the tickets. The connection from Locarno to Bellinzona is with the S-20 local train that costs 8.80 CHF and you just take the one that gets you to Bellinzona in time for your train from Bellinzona. It is a 24 minute ride and trains go every 30 minutes at 5 and 35 past the hour.

It is always best to buy tickets from the people who operate the trains. In this case SBB and Trenitalia.

Thank you for the reassurance and guidance!