Swiss Travel Pass Flex: choosing days

I would be very grateful to know the answer to this question, please. If I buy a Swiss Travel Pass Flex, do I have to decide in advance which days I would like to travel, or can I decide on the day(s) later, depending on the weather/mood of the group that day?

Hi Ealingmum, welcome to MySwissAlps!

No, you can choose the days as you go. They will be asking for a start date when you buy, but that's only the day you can start using the pass. You don't have to start that day. Please see myswissalps.com/ swisstravelpassflex/ price for purchase options.

Thankyou for your very helpful and speedy response!