Additional documents required by tourists
If you enter the Schengen area as a tourist, you may need to provide additional documents at the border. As well as a valid return or onward ticket, when travelling to Spain you could be asked to show:
You have enough money for your stayProof of accommodation for your stay, for example:
A hotel booking confirmation
Proof of address if visiting your own property (such as second home)
An invitation or proof of address if staying with a third party, friends or family, such as a ‘carta de invitation’ completed by your hosts.