Question

Best cheap way to go from Barcelona to Madrid overnight ?

Location

Country: Spain

Answers

Take the train or a bus. You may check flights since they can be very cheap if you do it with time and you are flexible,
you can take both train or bus, and the prize depends a lot on the offers you can find, I mean, train is not always more expensive than bus. Check this websites: (they got train offers), (bus), and (official train company)
Bus is probably the cheapest way if you are planning to travel overnight. Try

I don't think there are trains doing Barcelona-Madrid overnight anymore as now it seems all the trains are AVE (fast speed) and the price is similar to a regular airline.

It is also true that you might be able to find good airline deals if you plan it ahead of time or you don't mind waking up very early in the morning to catch the airplane.
Flights can be very cheap depending how far in advnce you book them. I suggest you take a look immediately and try and save yourself a few pounds.

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