Brits travelling to Spain now face limits on how much they can drink in a crackdown on drunken behaviour.
Thomas Cook has warned holidaymakers who have booked an all-inclusive trip that an alcohol cap will be in place.
The rule will affect tourists heading to the popular holiday spots of Magaluf, Majorca and some parts of Ibiza.
The government of the Balearic Islands say they want to improve the image of the party resorts, which have a reputation for boozy behaviour.
What are the new rules?
The alcohol crackdown means that holidaymakers on all-inclusive breaks will face a six-drink-a-day alcohol limit, instead of having free-flowing drinks all day.
Tourists will now be limited to three free tipples at lunch and three with their evening meal.
Travel agent Thomas Cook alerted customers to the changes in an email update on package holidays.
The email read: “Please be advised that a decree has been issued by the Balearic Government on a new restriction for All Inclusive meal option.
"There is a maximum of six alcoholic drinks per person per day that can be served and these drinks will be provided only during lunch and dinner ( 3 each).
"Please be aware that Magalluf, El Arenal, Playa de Palma in Majorca and Sant Antoni in Ibiza, there is new restriction on All Inclusive."
The Balearic government has also put a stop to pub crawls, the sale of alcohol in shops between 9.30pm and 8am and advertising party boats in some areas.
Balearic Islands Tourism minister Iago Negueruela previously said: “We want British tourists - we don't want this type of tourism.
"British tourism is essential for our islands. We share with the British government the view that some images of British tourists are embarrassing. We want to put a stop to bad behaviour.
"We will increase the police presence in these areas and the number of inspectors - we will have zero tolerance for tourism excesses."
Travel association ABTA has backed the alcohol limit, saying it "strongly supports" the new rules.
A spokesman said: "ABTA will continue to engage with the Balearic Islands Government, ABTA Members and other parties, to encourage clear communication and exchange of information, in order to ensure holidaymakers travelling to hotels in the designated areas enjoy a positive customer experience."