Rental income tax is a bit complicated subject in Turkey and might need professional guidance in order to reduce the taxes to be paid in legal ways. The regulations are changing while renting a residential unit or a commercial unit. In addition, there are two ways to calculate the tax as you will be choosing the one which is more beneficial for you. Again the tax to be paid is changing with progressive increases between %15 and %35 as shown below. However, there will be deductions in many cases and with the chosen calculation system, the percentages will be less in reality. Firstly you can take %25 of your income out of calculation. From the remaining amount, you pay taxes given below.
Up to 14.800 TL : %15
For 14800 TL the tax is 2.220 TL, from 14.800 TL to 34.000 TL : %20
For 34.000 TL the tax is 6.060 TL, from 34.000 TL to 80.000 TL : %27
For 80.000 TL the tax is 18.480 TL, over 80.000 TL : %35