I already have a ticket and want to book a seat reservation as well. Can I do that?

Reserving a seat after booking is possible in most cases. However, there are differences per train and ticket:
 
  • TGV, Eurostar and ÖBB Nightjet
    For TGV, Eurostar and ÖBB Nightjet, a reservation is required and included in the ticket. A seat or berth is automatically reserved when booking. The coach number and seat number are indicated on your ticket.
     
  • ICE International and Intercity Berlin
    For ICE International to Germany / Switzerland and for Intercity Berlin, a seat reservation is not mandatory. However, we do recommend that you make a reservation because of possible crowds on the train. It is most convenient to make a seat reservation while booking your ticket, but adding a separate seat reservation later is also possible. A separate seat reservation in 2nd class costs € 4,90 and in 1st class € 5,90 per person each way, plus a € 5 booking fee. At Where can I make a reservation below you can find the points of sale.
     
  • Intercity Brussels
    A seat reservation is not possible in Intercity Brussels, on this train there is free choice of seat.
     
  • Interrail & Eurail
    Reservations are not included with an Interrail or Eurail Pass. For high-speed trains such as TGV, Eurostar and ÖBB Nightjet, it is mandatory to purchase a reservation for a special Railpass fare. These tickets are specifically for Interrail or Eurail Pass holders and are offered at a reduced rate. The price varies per train. Please note: These tickets are available in limited numbers, we recommend that you book well in advance. This is possible at the points of sale below and at interrail.eu.
 
Where can I make a reservation
You can book a separate reservation for a seat:

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