We will be in Munich soon and had planned to take a day trip to Innsbruck if there was good weather. For 3 adults the price of train tickets seems pretty high! We can’t use the Bayern tickets because we will be going into Austria. Am I missing something to find a reasonable price (less than $100 per person round trip.)
The Regioticket Werdenfels is a day pass for 1-5 persons for travel to Innsbruck and back using regional trains via Garmisch-Partenkirchen (not a high-speed train route) and is priced at €64/3 adults; description on this page:
https://www.discover-bavaria.com/tickets
Reservations are not possible with this pass (as with the Bayern Ticket and other day passes) and it is non-refundable. Buy it on the morning of the day you wish to travel from a ticket machine in Munich.
German Rail Pass allows trips to Innsbruck, Salzburg, Basel, and cities in Italy. The fare otherwise (non-rail pass tix), depends on the time of day you travel. Times of day when business persons are going to/from work have the highest cost fares. Catch a train 10 mins earlier or later and it's 1/4 the cost. Check the Deutsche Bahn schedule. Example: a 0930hrs train on DB costs 22 euro. Depending on everyone's age, there are also senior discounts.
https://int.bahn.de/en/
The ticketing system is a bit complicated...
The variable-price tickets Kim703 suggests are called "Sparpreis" or saver fare tickets. These are one-way discounted fares are for the long-distance trains (like the RJ trains on this route) and are non-refundable and train-specific; the sooner you buy, the greater the likelihood of getting a low fare like €22 each. (The same long-distance trains can be used with a full-fare "Flexpreis" ticket, which is refundable, costs €46 ea. for your route, and which permits you to use ANY long-distance train for the specifiec route on a given day.)
https://int.bahn.de/en/offers/saver-fare-flexible-fare/super-saver-fare
Note that a daytrip will require two one-way tickets each, whether Sparpreis or Flexpreis, for these long-distance trains.
Any day trip done only by REGIONAL train (BRB, REX, CJX) can be carried out with a day pass like the Regioticket Werdenfels, which covers multiple trips all day long and will cover you in both directions; it is non-refundable, but it has the same flexibility that a flexpreis ticket does for the long-distance train: you are not required to keep a specific train schedule. The price of this day pass is the same, no matter when you choose to buy it, and is always available at that same price on the day of travel. Riding the long-distance trains with this ticket is not possible, however.