Wolves will only be allowed to register 23 players if they qualify for the Champions League next season, after they failed to meet Uefa's Financial Fair Play target.
Wolves beat Olympiakos to reach the last eight of the Europa League on Wednesday.
It is the first time Wolves have reached the quarter-finals of a European competition in 48 years.
Winning the tournament would earn them a spot in the 2020-21 Champions League.
However, even if they manage it they will not be able to register a full quota of 25 'A List' players as punishment for spending too much.
European football's governing body Uefa revealed the information after confirming it had reached a settlement agreement with Wolves, who play Sevilla in Duisburg on Tuesday.
In addition, Wolves have agreed to report "a maximum break-even deficit of €30m (£27.1m) in the financial year ending in 2020 and to finally reach, in the 2021/22 season, an aggregate break-even result for the financial years ending in 2019, 2020 and 2021".