A Spain Airport Transit Visa is a permit to stop at a Spanish airport, without leaving the international airport area, in order to get another flight, to your non-Schengen destination country.
It permits you to remain in that airport for a maximum of 24 hours. Before starting the procedures to get such a visa, first make sure to check whether you need a Spain Airport Transit Visa or not.
Application for a Spain Airport Transit Visa
The Spanish Airport Transit Visa is the easiest visa for Spain to get. The application procedures are very similar, almost identical, as when applying for a Spain short-stay visa. Yet, getting an airport visa is quite easier.