If you’re buying a ticket, I’d do it ASAP as the special fares might sell out. If you’re using a rail pass and buying “just a reservation” I’d wait. The seats for pass holders aren’t really limited. What’s limited is the seats available at the specially reduced pass holder fare. You’re going to pay at least full price and maybe more than double full price if you try to buy in advance, so I’d wait. Four days in advance should be plenty of time — even to get pass holder fare and if those are sold out, you can just pay full price for the reservation.

Check www.Thalys.com You may be able to buy a resonably priced reservation or find a special fare where the ticket, with reservation, will cost only a few euros more than the cost of just the reservation.

Ok great, thanks.

We are using a day on our pass for this day, so just need the reservation. So I will do that when I first get to Paris then. Thank you!

If you find a cheap special fare, it could be significantly cheaper than using a day of the railpass and buying a reservation. You’d then have an extra rail day for something else.

BTW, Paris to Brugge via Lille will save you the expensive Thalys reservation. You’ll only need a 4 or 5 euro TGV reservation. It can be just as fast as (or even a couple of minutes faster than) the Thalys train, but you’ll need to make two connections (Lille and Brussels) instead of just one.

Oldlady, once again you saved me some money! Ended up booking Paris-Arras for 12 euro! Amazing price! So we will get to see Vimy Ridge that morning and then when we are done we will take a regional train to Lille. I will not book this as I assume it’s probably not very expensive (plus we do not know how long we will be at Vimy so don’t want to have to rush back for a train).

So now this extra day will be used fro Rome-Naples! (Which apparently is 30 something euro)

I see there is a eurostar italia that I want to take, so I will just reserve that right when we get to Rome.

Thanks!!