Though the tax year already started with 20%, based on Law No 7316, as of today, 2021's (current year) corporate tax rate has been increased to 25%
Turkey applied 22% corporate income tax rate for the years of 2018 - 2019 and 2020
Based on previous legislation, 2021's income tax came down to 20% but as mentioned above, a new Law passed which foresees;
2021 corporate income tax as 25% and
2022 corporate income tax as 23%
Keep safe until next amendment!