Non-EU passport holders entering Spain as tourists must show a confirmation of their rental reservation or a letter of invitation from their host, which must be processed by local police.
The UK government also advises tourists to have a valid onward or return ticket, as well as to check that their passport is up to date.
Tourists traveling to Spanish regions for up to 90 days could face a fine of £8,000 if they do not provide proof of their stay.
Non-resident Spanish homeowners and guests who stay beyond the 90-day limit could be fined up to €10,000.
Regulations to curb anti-social behavior have been in place since 2022 in the Balearic Islands and bans on drunk British tourists breaking the rules are now being considered.