City said they were "disappointed and surprised" by the Premier League's decision to find them guilty of breaking financial regulations between 2009 and 2018.
"Manchester City FC will now pursue the appeal avenues open to it, on the basis that the opinion contains clear material errors, of law, principle and fact, and is unsafe," the club said in a statement.
According to Premier League rules, the sanction can vary from a points deduction, a fine or even expulsion from the division.
Everton and Nottingham Forest were handed points deductions in the 2023/24 season for single breaches of financial sustainability rules.
On that basis, City would face likely relegation if the same penalty is applied for over 100 charges.