Inter have been fined €6 million for breaching Financial Fair Play regulations and could pay a further €14m dependant on their adherence to a list of financial conditions.
The Serie A club, along with nine other teams, were under investigation over their non-compliance with break-even rules enforced by the governing body and now face a list of sanctions.
Should they qualify for Europe this season, Inter will only be allowed to register 21 players for the 2015-16 campaign, rather than the usual maximum 25-man squad, with that number rising to 22 the season after.
The limit will be lifted in 2017-18 if the Nerazzurri comply with regulations, which include reporting a break-even deficit of €30m for the financial year ending 2016.
Also facing punishment are another Italian club, Roma, who will pay a €2m fine, and potentially an additional €4m if they flout guidelines again over the next three seasons.
Like Inter, the Giallorossi's European squad will also be trimmed, with their A-list restricted to 22 players next season, though that restriction will be lifted in 2016-17 if their finances are brought in line.
The number of new registrations allowed on the club's A-list is capped as well, dependant on their net transfer position in each window.
Ligue 1 side Monaco could pay a total fine of up to €13m, €3m of which will be paid in full , with the remaining €10m conditional depending on if they adhere to economic measures.
Like Rudi Garcia's Roma, Leonardo Jardim will only have 22 players to choose from in Europe in 2015-16, with that enforcement being lifted providing they stay in line with the governing body's financial rules.
Monaco have also agreed to report a maximum break-even deficit of €15m for the financial years ending in 2015 and 2016 and no break-even deficit for the financial year ending in 2017.
Seven other clubs - Sporting Lisbon, Besiktas, Lokomotiv Moscow, FC Krasnodar, FC Rostov, Kardemir Karabukspor and CSKA Sofia - have been punished with varying degrees of severity.