Yes, any train or ferry with a discount means you won't need a travel day. It saves you one to get even more out of your Interrail Pass! The only requirement is that it falls within the validity of your Pass, but I'm sure that won't be a problem for you.

Hello Mattheas,

Thank you for your reply!!

Hi,  I’ve read this thread which is very helpful, I just some more help with Stena Line Ferries.  I have booked a night sailing from Hook of Holland to Harwich with a 30%discount.  My understanding was that this does not count as a travel day.  However I have read on the Interail website that:

When traveling by night ferry (Superfast, Minoan or Blue Star Ferries) you have to use a travel day and fill in the day of departure in your travel calendar. If you are still on this ferry after midnight, you don't have to use a second travel day, unless you board a second ferry.

https://www.interrail.eu/en/plan-your-trip/tips-and-tricks/trains-europe/ferries

However, I am travelling by Stena Line not “Superfast, Minoan or Blue Star ferries”? So, does any one know if my ferry journey counts as a travel day? or does not count as a travel day?

Many thanks

@MeganM 

Only travels where you get a 100% discount on the ticket (not on the reservation or any surchages) count as travel days.

Thank you.  Do you mean that my overnight ferry crossing does not count as a travel day?

No, you don’t need a travel day for this...

Thanks