In Türkiye, inflation data plays a key role in determining the maximum allowable rent increases each month. These figures, published by the Turkish Statistical Institute (TÜİK) during the first week of every month, guide both tenants and landlords in adjusting rental prices within legal limits.

On August 4, 2025, TÜİK released the official Consumer Price Index (CPI) figures that determine the cap on rent increases for August 2025. According to this data, the maximum rent increase rate allowed in Türkiye for August 2025 is 41.13%, based on the twelve-month average change in CPI.

CPI Developments in Türkiye – July 2025

The CPI figures are based on 2003=100 index values. As of July 2025, the changes in CPI are as follows:

  • Monthly change: +2.06% (compared to +1.37% in June 2025)

  • Change from the same month of the previous year: +33.52%

  • Change since December 2024: +19.08%

  • Twelve-month average change: +41.13%

This twelve-month average is the key figure used to calculate rent increases for both residential and commercial leases in Türkiye.

What Is the Legal Basis for Rent Increase Limits in Türkiye?

According to Article 343 of the Turkish Code of Obligations, changes to lease agreements that are unfavorable to the tenant—apart from rent adjustments—are not legally valid.

Article 344 of the same law outlines how rent adjustments should be determined. It states:

“Agreements between parties regarding rent increases during renewed rental periods are valid only if the increase does not exceed the twelve-month average change in the consumer price index. This rule also applies to rental agreements exceeding one year in duration.”

Following an amendment on January 17, 2019 (Law No. 7161), the reference used for determining rent increases was updated from the Producer Price Index (PPI) to the twelve-month average of the Consumer Price Index (CPI).

If no agreement exists between the landlord and tenant, the rent adjustment is determined by the court, based on the property’s condition and in line with the CPI twelve-month average.

Can a Landlord Exceed the Legal Rent Increase Limit?

Under current Turkish law, landlords cannot unilaterally impose a rent increase above the CPI twelve-month average rate, which is 41.13% for August 2025.

However, this limit is not absolute. If both parties mutually agree, they may set a rent increase rate either above or below the legal ceiling. Absent such an agreement, the legal maximum prevails.

Conclusion:

In Türkiye, the CPI-based rent increase system protects tenants from excessive hikes while giving landlords a clear and lawful framework. For August 2025, the legally enforceable ceiling is set at 41.13%, a figure every tenant and property owner should be aware of.

Legal Notice: The information in this article is intended for information purposes only. It is not intended for professional information purposes specific to a person or an institution. Every institution has different requirements because of its own circumstances even though they bear a resemblance to each other. Consequently, it is your interest to consult on an expert before taking a decision based on information stated in this article and putting into practice. Neither Karen Audit nor related person or institutions are not responsible for any damages or losses that might occur in consequence of the use of the information in this article by private or formal, real or legal person and institutions.