Train Tirano to Zurich

The Saver Day Pass will cover your train, boat and bus travel throughout Switzerland for the day it is valid. Only the scenic trains require the purchase of a seat reservation. So, the reservations you have bought for Tirano to Chur take care of that. You can use the Saver Day Pass to continue on the same day from Chur to Zurich and that leg will not require a seat reservation. Keep in mind the Saver Day Pass is nonrefundable and cannot be exchanged.
You are in for quite a spectacular train ride with the route from Tirano to Thusis designated a World Heritage Site by UNESCO.
Have a great trip!

Chur to Zurich is just a regular IC train. If you want a seat reservation, you can buy it for 5 CHF. But seriously, nobody buys seat reservations for that leg. Trains are very frequent Chur to Zurich.

One other point....

As I recall, the panoramic Bernina Express arrives in Chur after 18:00, so that will mean a somewhat late arrival in Zürich. That will be a bit of a long travel day. When I did that trip, I decided to spend a couple of nights in Chur to do some exploring, and quite enjoyed that. I had a few interesting travel experiences there.

Thank you so much for the information! It was all very helpful. Just one more question about the saver pass. We do not need any other card like the GA travel card to purchase the saver pass fare correct? It came up as available so I'm assuming we can purchase.

Nothing else needed except your passport to act as your ID, since the Saver Day Pass is in your name and not transferrable. Should be 52 CHF 2nd class without a Half Fare Card.

Great, thank you!