Question about Deutsche Bahn flexibility

It depends on what kind of ticket you have. There are cheap ones that are only valid on a certain departure, and more expensive ones that allow you to take any train you want that day.

The default in Germany is for tickets to be flexible. Ie. a ticket is for a route, not a train, just like in the UK. And just like in the UK you can get advance discounted fares that do lock you in to a train, but are cheaper. Because of the priced difference most people end up buying discounted tickets. But if you buy a flexible ticket you can take any train on the route.

The main difference with the UK is that DB, like most continental railways, practices "single leg pricing", where a return ticket is just two singles bought together. So you do not have the cheap returns you have in the UK. Als there are no flexible discounted tickets like your off-peak tickets.

One other thing to be aware of with DB is that as soon as the schedule of the train you selected during booking changes by as much as a nanosecond they will send you verbose and confusing emails telling you that "your trip is no longer possible" and that you need to look up an alternative connection, and that you can now take any train on your route. Often this comes with a link that leads you to a page that will confuse you even more... Its an art DB really masters.

Ignore these mails, except for the bit where they tell you that your ticket is now a flexible one. Hurray. You have bought a flexible ticket at a discounted price. Now just go on www.bahn.de the day before your travel, and find yourself a train to travel on.

Wengenk described the "cancelled journey" loophole better than I probably could, but I did use that exception once or twice on a recent trip. It also applies to missed connections due to late trains (which was most of the trains I took). And yeah, for anyone trying to read through the documents and links sent with the cancellation, good luck! If you have questions, best to go to a manned service counter, and have them print off a new suggested itinerary.

There are some catches though, if you had reservations on any of the scheduled trains, those are lost (Maybe you can apply for refund), and if the trip is International, legs in those other countries can be completely cancelled, leaving you to purchase those anew. In my case, since the other legs were in the Netherlands, any train on the route works there as well.

Thank you so much guys, these are really great answers!

Wengen, I laughed so hard at your description of DB's emails, but it was also so true. :-) That happened to me a couple of years ago and yes, DB has mastered the art of confusion very well. Luckily I came here for advice at the time, and was told to just pick a train that would get me there. It wound up being one that had fewer transfers and got me to my destination an hour earlier than the previous train, so I lucked out.

Hurray. You have bought a flexible ticket at a discounted price.

Hilarious and great DB info. I love winning the "rescheduled ticket" lottery!

This page of Deutsche Bahn explains the three fare / ticket types for single and / or return tickets.
https://int.bahn.de/en/offers/saver-flexible-fares

Total freedom travelers have with Flexible Fare.

they will send you verbose and confusing emails telling you that "your
trip is no longer possible"

I got one of these last year. Since I was already in Germany I simply went to a DB office to understand what I needed to do. The agent quickly rebooked me. When I saw the new time, I was confused as it was 5 or 6 hours different from my original trip and I knew there were other trains. The agent had booked the new trip based upon my home time in the US (which was on my original paperwork from DB). Quickly got a better time schedule.

BTW, I've never had a bad interaction with a DB agent. I think they understand the most of us from the US only ride trains outside our home country.