At the end of September/early October myself, my wife and our son will be traveling in Germany and The Czech Republic. We are looking to take trains from Berlin to Dresden, Dresden to Prague, and Prague to Munich. Should we purchase all the tickets ahead of time or wait until we are in Germany and The Czech Republic to buy? I've been looking online and there seems to be many places to get tickets, Omio, Rail.ninja, raileurope, etc. anyone have any experience with using one website over another? Thank you.
The cheapest place to buy tickets online will be the website of the company operating the trains. Occasionally that's impractical (your credit card might be declined, for example), in which case you have a choice between using one of the third-party websites like those you've mentioned (which will likely cost more, perhaps quite a bit more) or waiting until you get to Europe, at which point it will probably be too late to find discounted tickets. For some routings the early-purchase discounts can be substantial, but often those tickets are non-refundable/non-changeable, which is a just a bit riskier this year than usual!
The website Seat61.com has a lot of information about European trains and buying tickets. Here's the information on train travel in Germany: https://www.seat61.com/train-travel-in-germany.htm
And here's the information on trains from Prague to other countries, including Germany: https://www.seat61.com/international-trains/trains-from-Prague.htm
I haven't traveled between Germany and Czechia, but I know some of the folks on the forum have. I hope you'll get some information from them based on experience.
You might also look at getting the BahnCard which, when used on the Deutsch Bshn site can save you money. There's another post indicating the 25% discount card is on sale for €9.90, rather than €19.90, making it even easier to justify.
Anticipating a question, I was able to use my BahnCard to buy discounted tickets from Germany to Poland, so you may also be able to get discounts on your tickets from Germany to Czech Republic. Though it is worth checking the Czech train site because as was mentioned above, the tickets may be cheaper there, even with the discount. My ticket from Dresden to Poland was cheaper from the DB site with the BahnCard discount.
If you buy the ticket for Prague to Munich from the German Railway, Deutsche Bahn, they charge 40 EUR for a nonrefundable ticket. That is about $48 US. If you buy it from the Czech Railway, Ceske Drahy, they charge 754 CZK for a train specific ticket. That is about $35 US and the ticket can be refunded up to the day before for a $3.50 fee per person. Exact same trains, so there is some advantage to buying it in the Czech Republic.
Make sure you understand the conditions for the BahnCard that I posted on the thread linked to by CWSocial, above. It's a subscription and keeps renewing annually until you cancel it in writing.
With advance purchase (currently less than 1 week), Super Saver ticket for the direct EC (takes 1:51) from Berlin to Dresden can be as low as 17,90€.
The advance purchase ticket from the Bahn from Dresden to Prague starts at 13,90€.
Lee makes an excellent point about the subscription nature of the trial BahnCard. I notified them of my cancellation via email within the prescribed time period and the cancellation was handled efficiently and effectively.
Pre-Covid, all-reserved seat trains were common, which could book up completely in summer, or require two travelers to sit in different cars. Advance purchase tickets, with restrictions, are almost always cheaper. Sometimes (especially on premium services or high-speed routes), they are a lot cheaper. It’s not as hard as you think to use the national rail sites, and print a barcoded ticket before you leave the USA. See Rick’s travel tips, blue menu top left.
I think you should buy tickets on the spot. So you can safely visit beautiful places.
we've used thetrainline.com in the past. They used to sell at the same price as the national operator, I think they have small markups on some routes now. They show all the trains, which raileurope does not. raileurope will only allow you to use the US site and it only shows some of the trains, typically the more expensive ones.
https://www.bahn.com/ is useful to bookmark for train travel. They have the schedules for just about every train in Europe, even if they don't sell the tickets for the journey.
Buy as you go or in advance is a perpetual question. It costs more to buy as you go, but it gives flexibility. People can decide differently.