UK GOVERNMENT ANNOUNCEMENT
An update on travelling into the Schengen zone (Which includes Spain) from Jan 1st 2021.
This confirms that the 90 day in a rolling 180 maximum stay starts from Jan 1st. be aware also of the following:-
To stay for longer, to work or study, for business travel or for other reasons, you will need to meet the entry requirements set out by Spain. This could mean applying for a visa and/or work permit. You should check with the Spanish Embassy what type of visa and/or work permit, if any, you will need.
If you are in Spain with a visa or permit, your stay will not count towards the 90-day limit
The 90-day limit for visa-free travel will begin on 1 January 2021. Any days you stay in Spain or other Schengen countries before 1 January 2021 will not count towards the 90-day limit.
At border control for Spain, you may need to:-
Show a return or onward ticket
Show you have enough money for your stay, and
Use separate lanes from EU, EEA and Swiss citizens when queueing
Your passport may be stamped on entry and exit.