Hi @El Ra did you book to travel from Paris to Amsterdam on the Thalys (high-speed train) or on normal trains? If the latter, then you don’t need a reservation on the sections from Lille to Antwerp Centraal (Anvers/Antwerpen in French/Dutch) and from Antwerp Centraal to Amsterdam. You can just get on the train with your activated Interrail/Eurail pass. So it might be you only need a seat reservation on the (TER?) train from Paris to Lille.

Without details I think it more likely the reservation is for a TGV to Lille Europe. The Lille - Antwerp regional train leaves from Lille Flanders station which is about 10 min walk or 1 tram stop from Lille Europe.

Who did you book with? 

Ok. Thank you for the information. I booked 1st class with the global pass but it appears that Thalys is already sold out for that day during the morning or either not working so I will have to take the regular interrail trains. Thank you so much for your help!

@El Ra you’re welcome! It’s worth mentioning that there’s a direct non-Thalys train (called Intercity Brussel) from Bruxelles-Midi to Amsterdam Centraal pretty much every hour all through the day, and you don’t need a reservation to go on it. It doesn’t take that much longer than the Thalys and it goes through Antwerp, so if you can get a regular TGV from Lille→Brussels (or change the reservation from Paris to go to Brussels) it won’t take that much longer to get to Amsterdam.

There’s usually more availability Brussels  Paris, so if I’m travelling from Amsterdam (where I live) to Paris I always check if there are seats on that part of the route if I can’t get a seat reservation for the whole route. I also do that for Brussels  London as sometimes there are seats available between those two cities, even on the same trains which are full Amsterdam  London - I think they put passengers for different destinations in different parts of the train. 

Awesome...thanks for the info!

Actually right now I have just boarded the direct TGV from P to L-which this time ends even at Flandres (Vlaanderen, the old station where the BE trains also start) and intend to make nearly same trip-not as far as my former working place AMS, as I am not tourist.

You chnage hence in regional trains without any RES needed-or even possible-via Antwerpen (admire the railway cathedral) and probably also Kortrijk.

It is often surprising for those who think trains are like planes: but well over 90-95% of all trains here in EUR run without any RES nor even chance to do so. Just board (there will be no advance checks) and find seat. Sooner or later-or never, some one who checks will pass by.