The punishment, handed down by the Club Financial Control Body (CFCB) relates to the period up until the end of the 2023-24 season when the club were found to be over the governing body's spending limits.
Villa have been fined five million Euros for breaching Uefa's version of profit and sustainability, which allows clubs to lose a maximum of £55m over a three-year period.
They have been hit with a further six million Euro penalty by exceeding the squad cost rules which limit the amount clubs can spend on transfer fees, wages and agents's fees in relation to their revenue.
Villa, who have been dialogue with Uefa since before the end of last year, will also face an extra five million Euro fine for each following season they fail to comply with the rules.
Despite the sanction, the club are confident in their ability to comply from now on and do not believe it will require a "fire sale" of star players in order to do so, with the belief Unai Emery will still be able to build a competitive squad this summer.
Costs have already been trimmed with playmaker Philippe Coutinho having been moved off the wage bill permanently, while youngster Kaine Kesler-Hayden moved to Coventry for a fee approaching £5m.
Forward Louie Barry is also expected to leave this summer, despite the collapse of his proposed move to Hull.
Though Villa will not be allowed to increase their squad costs this summer, as part of the sanction, the fact Marcus Rashford and Marco Asensio's combined salaries of more than £500,000-a-week were included in their 2024-25 squad cost means they still have a relatively high ceiling.
Villa managed to comply with the Premier League's PSR rules by selling their women's team but that profit cannot be used under Uefa's rules