It is up to the various carriers to decide when train tickets go on sale, but this is not the same for all international trains.

Eurostar to Belgium/France:
- Eurostar to Belgium/France: 4 months before departure
- Eurostar Snow: booking from the beginning of September for the whole winter season
- Eurostar Sun: booking from the beginning of March for the whole summer season
Eurostar to London:
- Eurostar Amsterdam CS - London (direct train): 330 days before departure
- Eurostar and Intercity Brussels (transfer at Brussel-Zuid/Midi): 180 days before departure
- Eurostar to London and Eurostar to Belgium/France (transfer at Brussel-Zuid/Midi): 4 months before departure
Intercity Brussels: 335 days before departure
Intercity Berlin: 180 days before departure
ICE International: 180 days before departure

Check also the Questions and answers page about early bird booking.

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