
A rent determination lawsuit is filed particularly to redetermine the rent amount in renewed lease periods, in accordance with current market conditions. Upon the expiration of the 5-year period, landlords can apply to the court to increase the rent amount under certain conditions.
1. What are the Conditions for a Rent Determination Lawsuit Filed Due to the Expiration of the Five-Year Period?
Certain conditions must be met for a rent determination lawsuit to be filed. The main conditions required to file a rent determination lawsuit when the 5-year period expires are as follows:
Duration of the Lease Agreement: The term of the lease agreement must have exceeded 5 years or the lease agreement must have completed its fifth year. According to Articles 344 and 345 of the Turkish Code of Obligations, it is possible to update the rent amount in lease agreements lasting longer than 5 years or renewed at the end of 5 years.
Agreement Regarding the Rent Increase Rate: Even if a rent increase rate has been agreed upon between the parties, upon the expiration of the 5-year period, the court can determine a new rent amount without being limited to this rate. In this case, when determining the rent, the judge takes into account comparable rent amounts and current market conditions.
Legal Interest Requirement: The plaintiff property owner must be able to state the need for the rent amount to be adjusted according to market conditions. Particularly, a rent determination lawsuit can be filed if the tenant claims that the current rent amount is not in line with market conditions.
2. Is it Necessary to Send a Preliminary Warning Before Filing a Rent Determination Lawsuit?
In rent determination lawsuits filed after the expiration of the 5-year period, there is no obligation to give notice. If there is a lease agreement between the parties and the 5-year period has ended, the landlord (property owner) can directly file a rent determination lawsuit without sending a notice.
The Supreme Court has ruled that if there is a rent increase clause in the lease agreement, the landlord can file a lawsuit at the end of the term without needing to send a prior notice. This way, a rent determination lawsuit can be filed at any time from the date the contract is renewed, without the need for a notice.
3. When is the New Rent Amount Determined in a Rent Determination Lawsuit Filed Without Prior Notice Valid From?
If a rent determination lawsuit is filed without prior notice, the determined new rent amount is generally valid from the next rental period. However, in this case, in accordance with Article 345 of the Turkish Code of Obligations, the date of filing the lawsuit or the period for giving notice plays an important role in determining for which period the rent amount will be valid.
According to TCO 345: If a rent determination lawsuit is filed at least thirty days before the renewal date of the lease agreement, or if a notice containing a demand for a rent increase for the new period has been sent, the rent amount determined by the court will be valid from the beginning of the next rental period.
For example, if a 5-year lease agreement was initiated on 01.06.2019 and ended on 01.06.2024, the landlord can send a notice thirty days before or during this date to demand the rent amount that will be valid in the new period. However, if such a notice was not sent, the rent amount determined by the court will be valid from 01.06.2025.
4. Is a Warning Required if There is a Rent Increase Clause in the Contract?
If there is a provision regarding a rent increase in the lease agreement, there is no need to issue a warning to file a rent determination lawsuit at the end of the 5-year period. In this case, in accordance with the decisions of the Supreme Court, the landlord’s right to file a lawsuit to determine the new rent amount arises with the end of the term and the completion of the 5-year period.
The Supreme Court has stated that if there is an increase clause in the lease agreement and a rent determination lawsuit is to be filed after 5 years, the condition of a warning is not required. For example, in its decision numbered 2014/8948 E. and 2015/5710 K., the 6th Civil Chamber of the Supreme Court ruled that the landlord can file a rent determination lawsuit without the need for a warning at the end of the term.
In such a case, the new rent amount determined by the court will be valid from the beginning of the period when the 5-year term ended.
5. How Does the Judge Determine the New Rent Amount in a Rent Determination Lawsuit?
In rent determination lawsuits filed upon the expiration of the 5-year period, the judge considers multiple factors when determining the rent amount:
Comparable Rent Prices: The court makes an assessment by considering the rent prices of similar properties in the same region.
CPI Rate: There is no condition to consider the CPI rate in rent determination lawsuits to be filed after 5 years. However, the court may take the CPI rate into account along with other market conditions.
Equity Reduction: For long-term tenants, the court may apply an equity reduction of 10% to 20% from the determined rental fee. This is applied particularly when the tenant has occupied the same property for a long period and the rental fee is updated with a specific increase rate, to prevent an excessive burden on the tenant.
6. Is Amendment Possible in Rent Determination Lawsuits?
In rent determination lawsuits, the issue of amendment (ıslah), i.e., the subsequent alteration or increase of the lawsuit, is significant. Particularly in lawsuits for the determination of rental fees, the plaintiff may wish to subsequently increase the rental fee initially requested or to amend the petition. However, according to the established jurisprudence of the Court of Cassation, amendment is not possible in rent determination lawsuits.
The Court of Cassation has clearly stated that in rent determination lawsuits, the plaintiff cannot reserve their rights regarding the excess amount and cannot request an amendment. For example, in the decision of the General Assembly of Civil Chambers of the Court of Cassation, numbered 2017/2792 E. and 2021/267 K., it was stated that due to the nature of rent determination lawsuits, amendment is not possible, and the plaintiff must request a clear and specific rental fee in the petition.
Accordingly, when filing a rent determination lawsuit, the requested rental fee must be carefully determined and stated as a clear amount in the petition from the outset. This is because in such lawsuits, there is no possibility to increase the amount or make changes after the lawsuit has been filed.
Practical Advice: It is important for landlords to correctly determine their rent claims from the outset in these cases and to manage the process meticulously. In particular, comparable rent prices must be carefully researched, and the demanded rent amount should be determined in accordance with market conditions. In practice, the inability to reserve rights regarding the excess due to the lack of a right to amendment can lead to a loss of rights for landlords.
7. Is Mediation Mandatory in Rent Determination Lawsuits?
As of September 1, 2023, participation in the mediation process has become mandatory in rent determination lawsuits. The purpose of this regulation is to enable parties to reach a settlement before resorting to court proceedings. Now, before filing a rent determination lawsuit, the landlord and tenant must apply to a mediator and complete this process.
The mediation process usually takes three weeks, but this period can be extended by one week if an agreement cannot be reached. If a solution cannot be achieved through mediation, the parties can apply to the court. This new obligation offers landlords and tenants the opportunity to resolve disputes more quickly by accelerating the process and lightens the court’s workload. Therefore, those considering filing a rent determination lawsuit for rental agreements that have completed their 5-year term must first apply for mediation. Article suggestion.
Conclusion
In rent determination lawsuits filed after the expiration of the 5-year period, the landlord has the right to apply directly to the court without the need for a warning. In such cases, the new rent amount to be determined by the court may vary depending on the time of filing the lawsuit and the warning period. If the tenant is a long-standing tenant, an equity discount is applied to prevent the tenant from facing an excessive burden. Furthermore, the impossibility of amendment (rectification/correction) in rent determination lawsuits requires landlords to make their requests correctly and completely from the outset. Therefore, it is important for property owners to evaluate the process in detail and seek legal advice if necessary before filing a lawsuit.

Why Should Expert Opinion Be Sought?
Rent determination lawsuits are cases that require technical knowledge and legal experience. Incorrect determination of the rent amount, presentation of incomplete or erroneous precedents, or procedural errors made during the lawsuit process can lead to serious loss of rights for the property owner. For this reason, seeking legal support from a lawyer specialized in the field at the beginning of the process ensures that the most accurate outcome is reached in favor of the property owner.
Especially in high-population density, active real estate market regions such as Istanbul in general and its districts like Tuzla, Maltepe, Pendik, Kartal, as well as Gebze, Çayırova, and Darıca which are part of Kocaeli, rent prices can fluctuate every year, and regional precedent research is of great importance. In rent determination lawsuits filed in these regions, courts may use different evaluation criteria.

Keywords: Rent determination, 5-year period, Lawyer, Rent, Tenant, Landlord, Tuzla, Istanbul
IMPORTANT REMINDER: Rent determination lawsuits and the mediation process are procedures involving sensitive and technical details. Any error or deficiency made during this process can lead to loss of rights. Therefore, obtaining expert support is a critical step to avoid loss of rights and achieve the most accurate outcome. Working with a professional consultant will ensure that this process proceeds smoothly.


