Hi, I am so confused about train tickets from Brussels to Delft. The train schedule we want, which allows us 14 minutes rather than 6 minutes to transfer in Rotterdam, is run by 2 different train services - National Railway Company of Belgium (ECD 9535) for the international train and NS Intercity (3243). But when I go to each of their sites I cannot book the train times desired, only other options with either the 5 minute or much longer transfer times. Do I need to buy those tickets individually to get the trains we prefer?
What specific day or how far in advance are you trying to book this?
You should be able just book the whole journey on either the national railroad of the Netherlands site or the Belgium site.
https://www.ns.nl/en
https://www.belgiantrain.be/en
Only trains with a leg Brussels to Amsterdam operated by Eurostar need to be reserved in advance.
All others are fixed price and don't really sell out and the ticket is good for any train on the day and routes you are traveling on.
Since you are crossing the border, you want SNCB International https://www.b-europe.com/EN or NS International https://www.nsinternational.com/ to book.
The Brussels to Rotterdam leg could be on Eurostar, fast but costly, or you can select a route with just intercity trains, maybe with a change in Antwerp. As long as you select to see all options (not just fastest routes) you should see all the choices.
The other advantage of intercity trains, is that you can take any train that day, as well as stop and explore any town along the way, before getting to Delft. If any leg uses Eurostar, you are locked into that time and seat.
Since this is an international journey between Belgium and Netherlands, use this site:
https://www.b-europe.com/EN
Stay off of the Eurostar and save a lot of money and the journey is only 30 minutes longer.
The journey you are looking at costs 22.90 EUR for the date I looked at (Feb 20). In Rotterdam, you go from Track 12 to Track 9, meaning going down to the ground level, then walking a short distance to the stairs/escalator/elevator up to Track 9. 6 minutes should be doable, but if you miss it due to a late arriving train, just wait for the next one. There are like 12 trains every hour from Rotterdam to Delft, maybe on other tracks. It is only a 10 to 14 minute train ride from Rotterdam to Delft.
Further research indicates that almost all of the trains from Rotterdam to Deft use either Track 9 or Track 8 and these tracks share the same platform. So if you miss a train to Delft, there should be another train to Delft across the platform in 5 minutes.