Tipping is not a must in Spain, but it is quite common. About 5-10% of the bill is considered appropriate. In more upscale restaurants or for higher bills, 10-15% is more appropriate. Tipping should be as discreet as possible. This is probably why it is not customary in Spain to round up the bill amount and tell the waiter orally. The typical German or Austrian “stimmt so” is completely uncommon throughout Spain. After the bill is brought in on a small plate or in a leather folder, you either put in your EC/credit card or the amount in cash. The waitress then returns with the entire amount of money (“cambio”). When leaving the restaurant, it is customary to leave the tip, which you consider appropriate, on the table or on the plate or in the folder.