I'll be in Munich in May 2015 for about a week, traveling next to Zurich. Any recommendations on most budget friendly mode of transport between the two cities? I'm debating between taking a train or flying.
The price i checked for a bus was 20€ and the drive takes about 4 hours. If you take the train it will cost you around 40€ and it will take you about 4,5 hours to get there. The 40€ by train are the special fare, where you can only take the trains printed on your ticket and cant change them. So if something happens or is delayed and you cant get your connections, you probably have to buy another ticket. The bus will take you directly there and is also faster as the train, even that you will ride on some parts on the high speed train (ICE) but you will have to change trains or wait at a train station. It depends what you choose. If you choose the flexible train ticket, which allows you to take any train (diffrent times) to zurich, costs about 60€.
This prices are based on a one-way trip and are if you book a couple weeks ahead of your departure date. If you book just a day before, prices will get expensiver for bus and train.
I checked the prices on the german railroad website www.bahn.de but you might could google bus transfers from munich to zurich and get even a better deal. Key would be to book way in advance and not for a next day trip. This will save you money.
There is also some ridesharing services in germany, one which I know and offer my rides on is www.flinc.org. they have a smarthpone app for android and iphone. This will be probably the cheapest way to travel there, because I usually offer my rides for free, but also the most research intensive way. Because its not sure that somebody will go that way right when you want to go, but just for an extra alternative...
Hope that helped, if you have any questions, let me know and I am happy to help out.
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There is a Bus Service organised by the SBB (National Railway Company). There are many connections per day.
If traveling light, try looking at Ryan Air or Easy jet. They are excellent if you don't have to pay all the add on fees. Otherwise, definitely go via train!