Rent Determination Lawsuit in Turkey: Conditions, Filing Deadline and Results

A rent determination lawsuit in Turkey is a court action for residential and roofed commercial leases in which the court sets the rent payable for the new lease year, based on Articles 344 and 345 of the Turkish Code of Obligations (TCO). Both the landlord and the tenant may file it; when the landlord seeks a higher rent, it is often called a rent increase lawsuit in Turkey. The conditions are a valid and continuing lease, completed mandatory mediation and, for a determination based on comparable rents, a lease relationship that has completed five years. The lawsuit can be filed at any time, but for the decision to apply from the new lease period it must be filed at least thirty days before that period begins, or written notice must be given to the tenant within that time.

Under the Turkish Code of Obligations, lease agreements may be concluded for a fixed or an indefinite term. In practice in Turkey, residential and roofed commercial lease agreements are frequently concluded for one year and, unless the tenant terminates them in time, they are automatically extended for successive one-year terms. The parties may freely agree on the rent for the renewed period; however, under Article 344 TCO, neither such an agreement nor an increase clause in the contract may exceed the twelve-month average change in the Consumer Price Index (CPI) of the previous lease year. For this reason, the rent increase rate in Turkey remains within the statutory cap during the first five years, and a separate rent determination is usually unnecessary in periods covered by an increase clause.

Once the lease relationship in Turkey reaches five years, however, the rent may have fallen far behind market conditions. Article 344(3) TCO provides that, in leases longer than five years or renewed after five years, the judge sets the rent for the new lease year equitably, taking into account the CPI change, the condition of the property and comparable rents. At this stage, there are two possible routes:

1. Agreement of the parties: The tenant and the landlord may freely agree on the new rent, and the lease continues on the basis of the agreed amount.
2. Rent determination through the court: If no agreement is reached, the landlord or the tenant may file a rent determination lawsuit before the Civil Court of Peace in Turkey after completing mandatory mediation. The court sets a market-appropriate rent by considering comparable rents in the area, the features of the property and equity.

The institution of rent determination in Turkey arose from the need to update the rent in long-standing lease relationships according to market conditions. Its purpose is to protect the tenant against sudden and disproportionate increases while preventing the landlord from being bound for years to a rent whose value has eroded, thereby maintaining the balance between the parties.

What Is a Rent Determination Lawsuit in Turkey and Which Leases Does It Cover?

A rent determination lawsuit in Turkey is a constitutive action that allows the rent payable in the new lease year to be set by court decision when the tenant and the landlord cannot agree on the rent. It serves to bring the rent to a current, market-appropriate level in the face of changing economic conditions and plays an important role especially in long-term lease relationships.

1. Which Properties Can Be Subject to a Rent Determination Lawsuit in Turkey?

Under Turkish law, a rent determination lawsuit can only be filed for residential and roofed commercial leases within the scope of Article 344 of the Turkish Code of Obligations. It cannot be filed for leases of fields, land plots, unregistered land, properties with Ottoman title deeds, vehicles or other movable property. For this reason, consulting a real estate lawyer in Turkey is important to determine correctly whether the leased property qualifies as a residence or a roofed workplace.

• Covered Properties: Residences, roofed workplaces such as shops, offices, warehouses and stores in Turkey, together with the items the landlord provides for use with them.
• Excluded Properties: Unroofed property such as fields, gardens and open car parks, as well as leases of vehicles and other movables; in these contracts, the rent is determined under the general provisions and the contract. Whether a leased property falls within this scope is assessed by considering both the property type on the title deed and the intended use under the lease.
• Temporary Use Exception: Under Article 339(1) TCO, the lease of property allocated by its nature to temporary use for six months or less falls outside the protective rules on residential and roofed commercial leases in Turkey. For this reason, short-term holiday rentals in Turkey cannot be the subject of a rent determination lawsuit.

2. Does a Rent Determination Lawsuit in Turkey Collect Unpaid Rent?

Under Turkish law, a rent determination lawsuit only serves to determine the rent and does not include a claim to collect rent receivables. Consequently, court decisions on rent determination cannot be enforced through judgment-based execution proceedings in Turkey as regards the determined rent. If the landlord wishes to collect the difference based on the newly determined rent, a separate action for rent receivables must be filed or enforcement proceedings must be started under the general provisions.

In this process, the court in Turkey evaluates expert reports, comparable rents and property characteristics, including title deed records, mortgage information and other relevant data, in order to set a fair and equitable rent. A rent determination lawsuit thus provides an objective and judicial solution for adjusting the rent to current market conditions.

How Is Rent Determined by Mutual Agreement in Turkey?

In Turkey, the rent can also be updated without going to court if the tenant and the landlord agree on the rent for the new period. Under Article 344(3) TCO, a landlord whose lease has completed five years may request that the rent be brought in line with market value, and this determination may also be made by agreement between the parties.

1. Freedom of Contract Regarding Rent Determination in Turkey

Under the principle of freedom of contract, the parties in Turkey may arrange their lease relationship as they wish. In leases that have continued for five years or more, the landlord or the tenant may request that the new rent be set in light of current market conditions. Reaching an agreement before going to court both shortens the legal process and protects mutual interests.

This freedom has a limit under Turkish law: during the first five years of the lease, increase agreements for renewed periods cannot exceed the twelve-month average CPI change of the previous lease year under Article 344(1) TCO. Agreements up to this rate are valid, while the portion exceeding it does not bind the tenant.

2. Form of a Rent Determination Agreement in Turkey

In lease relationships in Turkey that have lasted five years or more, the parties may agree on the rent for the new lease period orally or in writing. Because the Turkish Code of Obligations does not, as a rule, impose a form requirement on lease agreements, oral agreements are also legally valid; however, since an oral agreement may be difficult to prove, drawing up a written document is very important in practice.

A written agreement clearly records the parties’ consensus and serves as evidence in any future dispute before Turkish courts. The rent provision should refer to the previous lease agreement and state clearly and precisely that “under the existing lease agreement between the parties, only the rent has been redetermined for the new period.” The main advantages of a written agreement are:

• Prevention of Disputes: The agreed rent cannot easily be called into question later.
• Ease of Proof: Even if one party denies the agreement, the written document can be submitted to the court as evidence.
• Preservation of the Contract: When it is clearly stated that only the rent has changed and all other terms remain valid, it is secured that no new lease agreement has been formed.

3. The Legal Nature of a Rent Determination Agreement in Turkey

Under Turkish law, if the parties have agreed only on the rent for the new period, this agreement does not change the other terms of the existing lease; it is a continuation of the existing contract and is not considered a new lease agreement. However, if changes are also made to matters such as the payment date, manner of use, deposit or eviction date in addition to the rent, it may be accepted that a new lease agreement independent of the old one has been concluded.

This distinction also directly affects how the five-year period is calculated in Turkey. The agreement should therefore expressly refer to the previous contract and state that only the rent has been updated; such wording creates a strong presumption that the agreement is limited to rent determination and that all other terms remain in force. For this reason, obtaining assistance from a rental law attorney in Turkey before drawing up an agreement on rent determination would be beneficial to protect the rights of the parties.

4. Rent Determination Through Actual Payment and Implied Acceptance in Turkey

Even without an express written or oral agreement, if the tenant in Turkey starts paying the rent requested by the landlord in the new period without any reservation, this is treated in practice as acceptance of the requested rent. In that case there is often no need to initiate a lawsuit for the new rent; even if a lawsuit has been filed, a tenant who paid the requested rent on time may not be held liable for litigation costs because they did not cause the lawsuit. The reverse situation does not have the same effect under Turkish law: if the tenant pays an increased amount of their own choosing and the landlord collects these payments without reservation, according to decisions of the General Assembly of Civil Chambers of the Turkish Court of Cassation this does not extinguish the landlord’s accrued right to sue and does not mean that a new lease on new terms has been concluded.

5. Practical Precautions for Rent Agreements in Turkey

Agreements made between the parties on rent determination under Turkish law should contain certain elements to prevent future disputes. The following precautions are recommended in practice:

• Written Form: The rent determination agreement should be made in writing and, if possible, reinforced by notarial certification.
• Reference to the Previous Contract: The written text should expressly refer to the old lease agreement and state that only the rent has been updated.
• Clear Declaration of Intent: The intentions of the parties should be expressed clearly and comprehensibly.
• Payment Description: The tenant may add wording such as “current rent for the 2026-2027 period” to the description of payments to facilitate proof of the actual determination.

Choosing the agreement route in Turkey avoids the time and cost of litigation and allows the lease relationship to continue amicably. However, it should be kept in mind that no new contract is formed when only the rent is regulated, whereas a new lease agreement may arise if other matters also change.

What Are the Conditions for Filing a Rent Determination Lawsuit in Turkey?

A rent determination lawsuit in Turkey can be filed at any time; however, for the claim to succeed and for the decision to apply from the requested period, there must be a valid lease relationship, a legal interest, completed mediation and, if a market-rate determination is sought, the five-year period must have expired. The timing of the lawsuit, the form of the notice and the nature of the contract also directly affect the outcome.

a) Existence of a Valid Lease Agreement in Turkey

To file a rent determination lawsuit in Turkey, there must first be a valid and continuing lease relationship between the parties. The agreement may be written or oral; however, written agreements are preferred in practice because they are easier to prove. If the lease relationship cannot be proven or ended before the lawsuit was filed, rent determination cannot be requested.

b) Existence of a Legal Interest Under Turkish Law

Under Article 114 of the Turkish Code of Civil Procedure (CCP), a legal interest is mandatory for filing a lawsuit. Legal interest is the legitimate and protectable benefit the claimant seeks to obtain by filing the action. The court assesses whether the claimant has a concrete need for rent determination; if there is no such interest, the case is dismissed on procedural grounds.

c) Five-Year Duration of the Lease Agreement in Turkey

For the rent to be set according to comparable rents and equity in Turkey, the lease relationship must have continued for five years or more. Under Article 344(3) TCO, the court cannot set the rent according to free-market conditions before the five-year period expires; during this period only limited increases linked to the CPI apply. In leases exceeding five years, however, the court may be approached even without an agreement between the parties.

d) Mandatory Mediation Requirement in Turkey

Since 1 September 2023, application to a mediator before filing a lawsuit has been a procedural requirement in disputes arising from lease relationships in Turkey. A rent determination lawsuit filed before mediation ends without agreement is dismissed on procedural grounds for lack of a cause-of-action requirement.

e) Requirement of Written Notice in Turkey

Under Turkish law, written notice is not a condition for filing a rent determination lawsuit but a condition for applying the rent set by the court from the beginning of the new lease period. If the lawsuit cannot be filed at least thirty days before the new period begins, the landlord should notify the tenant in writing that the rent will be increased at least thirty days before the new lease period starts; this notice ensures that, in a lawsuit filed by the end of the new period, the decision applies from the beginning of that period.

The following points should be observed in a written notice under Turkish law:

• Form of the Notice: The notice may be served through a notary public, by registered mail with return receipt or under the Turkish Notification Law; since the law prescribes no special form, what matters is that the notice is in writing, timely and provable.
• Content of the Notice: The notice should contain an express request for a rent increase and state the new rent requested.
• Increase Clause in the Contract: If the lease agreement contains a clause on rent increases for extended lease periods, no prior notice is needed for the decision to apply from the beginning of the new period.

When Can a Rent Determination Lawsuit Be Filed in Turkey?

Under Article 345(1) TCO, a rent determination lawsuit in Turkey can be filed at any time; what matters for the filing deadline is the lease period from which the rent set by the court will apply. The law links the timing of the lawsuit to the effect of the decision, so the term of the contract and whether it contains an increase clause must be examined before filing.

1. How Is the Filing Deadline for a Rent Increase Lawsuit Determined in Turkey?

Under Article 345(2) TCO, the rent set by the court applies from the beginning of the new lease period in Turkey in the following cases:

• Lawsuit Filed Thirty Days in Advance: If the lawsuit is filed at least thirty days before the new lease period begins, the decision applies from the beginning of that period.
• Written Notice Given Thirty Days in Advance: If the landlord notified the tenant in writing at least thirty days before the new lease period that the rent would be increased, the decision in a lawsuit filed by the end of the new period also applies from the beginning of that period.
• Increase Clause in the Contract: If the lease agreement contains a provision that the rent will be increased in the new lease period, the rent set in a lawsuit filed by the end of the new period applies from the beginning of that period.

If none of these three situations exists, the lawsuit can still be filed in Turkey; however, the rent set by the court applies only from the following lease period, not the period in which the lawsuit was filed. For example, if the lease year begins on 1 March each year and the contract has no increase clause, for the decision to apply from 1 March the lawsuit must be filed by 30 January at the latest or written notice must be given to the tenant by that date.

2. Timing for Leases of Five Years or More in Turkey

If the lease relationship in Turkey has completed five years, the landlord or the tenant may file a rent determination lawsuit to have the rent reset according to market conditions, even if the parties have not agreed on a new rent. In this case, the judge sets the rent for the new period equitably, taking into account:

• The twelve-month average change rate of the CPI,
• The location, condition and intended use of the leased property,
• Rental values of comparable properties in the same area,
• The principle of equity.

3. Timing for Leases Shorter Than Five Years in Turkey

If the lease in Turkey has not yet completed five years and the contract contains no rent increase clause, a rent determination lawsuit can still be filed, but the judge’s discretion is limited. Under Article 344(2) TCO, the judge sets the rent taking into account the condition of the property, provided that it does not exceed the twelve-month average CPI change of the previous lease year. In this case, comparable rents or market values cannot be taken as the basis; the determination covers an increase limited to the inflation rate.

4. Key Considerations Before Filing a Rent Determination Lawsuit in Turkey

A rent determination lawsuit in Turkey can be filed by both the tenant and the landlord. Before filing, the following points should be reviewed:

• The duration of the lease relationship (under or over five years?),
• Whether the contract contains a rent increase clause,
• Whether there is any written or oral agreement between the parties,
• Whether written notice of the new period’s increase was given in time,
• Whether mediation was properly completed.

Can a Rent Determination Lawsuit Be Filed in Turkey Before 5 Years?

Under Turkish law, if the lease agreement contains no rent increase clause, a rent determination lawsuit can be filed before five years have passed; however, the court can then only order an increase not exceeding the twelve-month average CPI change. In rent determination lawsuits filed before five years, the court does not take the market value of the property in Turkey or comparable rents as the basis; only an increase based on the inflation rate within legal limits can be made.

If the contract contains an increase clause for the first five years that does not exceed the CPI cap, that clause applies and filing a determination lawsuit before five years has no practical benefit in Turkey. If a new lease period begins during the proceedings, according to Turkish Court of Cassation practice the court asks the claimant whether they also request a determination for that new period and, if so, rules on it. The petition should therefore clearly state the lease period for which the lawsuit is filed.

What Is the Difference Between a Rent Determination Lawsuit and a Rent Adjustment Lawsuit in Turkey?

The other route for changing the rent in Turkey before five years have passed is a rent adjustment lawsuit based on excessive difficulty of performance under Article 138 TCO. If an extraordinary and unforeseeable situation arises after the contract is concluded, adaptation of the contract to the new conditions may be requested. The conditions for a rent adjustment lawsuit are:

• Extraordinary Situation: An extraordinary situation arises for a reason not attributable to the obligor after the contract was concluded (e.g. a severe economic crisis, pandemic or natural disaster).
• Unforeseeability: The situation was not foreseen and could not have been expected to be foreseen by the parties when the contract was concluded.
• Excessive Imbalance: The situation changes the facts existing at the time of the contract to the detriment of the obligor to an extent contrary to good faith.
• Performance or Reservation: The obligor has not yet performed or has performed while reserving the rights arising from excessive difficulty of performance.

If these conditions are met, the court in Turkey may be asked to adapt the contract by increasing or reducing the rent; if adaptation is not possible, withdrawal from or termination of the contract comes into play. Unlike the classic rent determination lawsuit, the rent adjustment lawsuit is based entirely on extraordinary circumstances and is not subject to the five-year requirement.

Both types of lawsuit are effective legal means in Turkey to eliminate legal uncertainties between tenants and landlords. Since these processes require technical and legal knowledge, obtaining professional support from an English-speaking lawyer in Turkey is important to protect tenant rights and to prevent possible loss of rights.

How Is the 5-Year Period Calculated in a Rent Increase Lawsuit in Turkey?

In a rent increase lawsuit in Turkey, the five-year period is, as a rule, calculated from the date of the first lease agreement with which the lease relationship began. Under Article 344(3) TCO, at least five years must have passed from that date before the judge can be asked to set the rent according to comparable rents.

1. Calculation Based on the First Lease Agreement in Turkey

Even if new lease agreements were drawn up every year while the lease relationship in Turkey continued, the five-year period is calculated from the date of the first lease agreement unless these agreements expressly state that the previous agreement was completely terminated and a new lease relationship was established on new terms. For example, if the lease relationship began on 01.01.2025, the five-year period expires on 01.01.2030, and a market-rate determination may be requested for the lease year starting on 01.01.2030.

2. Calculation Based on a Subsequently Signed Lease Agreement in Turkey

If a later lease agreement between the parties in Turkey expressly states that the previous agreement was terminated and a new lease relationship was established on new terms, the five-year period is, as a rule, calculated from the date of the new agreement. However, if it is claimed that the new agreement was drawn up only to put the existing relationship in writing and that the rent was not updated to the market rate at that time, the court must investigate this claim under Turkish law; if the rent in the renewed agreement does not reflect the market rate, an equitable determination may be made by taking into account the time elapsed since the start of the first agreement.

The current approach was set out by the Turkish Court of Cassation, 3rd Civil Chamber, Docket No. 2025/3450, Decision No. 2026/1141, dated 03.03.2026. In a commercial lease in Turkey that began in 2005, the first-instance court relied only on the contract renewed in 2018; the Chamber reversed that decision and required an additional expert report on whether the rent in the renewed contract reflected the market rate at that time. The decision stresses that if the renewed rent does not match comparable and market rents, the rent must be determined equitably by taking into account the time elapsed since the start of the first contract, even if five years have not passed since the renewed contract was signed.

Can a Rent Determination Lawsuit Be Filed for a 10-Year Lease in Turkey?

A rent determination lawsuit can be filed for a ten-year lease in Turkey; Article 344(3) TCO also allows the rent for the lease year following the fifth year to be set equitably by the judge in leases longer than five years. The fact that the contract is long-term and provides a fixed increase rate for each year does not prevent a determination based on comparable rents at the end of the fifth year.

In such contracts under Turkish law, the increase clause applies within the CPI cap during the first five years. For the lease year starting after five years, the landlord or the tenant may request a determination by arguing that the contractual rate does not reflect market conditions; the thirty-day period and notice rules in Article 345 TCO also apply to this lawsuit.

Can a New Rent Determination Lawsuit Be Filed After a Previous One in Turkey?

Article 344(3) of the Turkish Code of Obligations provides that a determination based on comparable rents and equity may be made not only at the end of the first five years but also “at the end of every five years thereafter”. Under the last sentence of the same paragraph, the rent so determined in the lease year after each five-year period may be changed in the following years under the principles of the preceding paragraphs, that is, within the CPI cap; once a new five-year period is completed, an equitable determination may be requested again.

In determination lawsuits filed in the intermediate years, the court can only make a determination within the CPI cap under Turkish law. Recording for which lease year the determination decision was given helps the landlord and the tenant avoid disputes when calculating the next five-year period.

Is It Necessary to File a Rent Determination Lawsuit at the End of 5 Years in Turkey?

Under Turkish law, completing five years in a lease relationship does not make a rent determination lawsuit mandatory; it only creates the possibility of requesting a market-rate determination. If there is a valid agreement between the parties that clearly specifies the annual rent increase rate, the parties may continue to apply this rate.

After five years, there are two possibilities depending on the parties’ situation in Turkey:

• Continuing to Apply the Increase Rate: Under the Turkish Code of Obligations, a fixed-term lease is deemed extended for successive one-year periods on the same terms unless the tenant gives notice in time. During these extensions, the increase rate in the contract remains valid, provided that it does not exceed the CPI cap. Therefore, if the parties are satisfied with the agreed rate and the lease continues without problems, a separate determination lawsuit may not be needed at the end of five years.
• Rent Falling Below the Market Rate: On the other hand, where the rent has fallen far below market value, economic conditions have changed significantly or a dispute over the rent has arisen, completing five years gives a legal basis for filing a rent determination lawsuit in Turkey. In such a case, either party may apply to the court, arguing that the contractual increase rate does not reflect current market conditions.

Is Sending a Notice to the Tenant Mandatory Before Filing a Rent Increase Lawsuit in Turkey?

As a rule, filing a rent determination lawsuit in Turkey does not depend on sending a notice. If the legal conditions are met, the landlord may file the lawsuit without sending a notice to the tenant; the importance of the notice is that it allows the decision to apply from the new period if the lawsuit is filed after that period has begun.

The following points are important regarding the effects and form of the notice under Turkish law:

• Timely Notice: Under Article 345(2) TCO, if the landlord has notified the tenant in writing at least thirty days before the new lease period that the rent will be increased, the landlord keeps the right to file a lawsuit until the end of the new period, and the rent set by the court applies from the beginning of that period.
• No Notice: If no notice was sent and the lawsuit was not filed at least thirty days before the new period, the decision applies only to the following lease period.
• Form of the Notice: The notice may be given through a notary public, by registered mail with return receipt or in writing delivered by hand against signature. Turkish law does not require the notice to be served through a notary or under the Notification Law; however, it is very important for validity and proof that the notice is in writing, timely and its delivery to the tenant can be proven.

How Is a Rent Determination Lawsuit Filed in Turkey?

A rent determination lawsuit in Turkey is filed by submitting a petition to the Civil Court of Peace after mandatory mediation has ended without agreement. Since a mandatory mediation process in Turkey has been required since 1 September 2023, applying directly to the court results in procedural dismissal. The following stages must be followed in order.

a. Application to a Mediator Before Filing a Rent Determination Lawsuit in Turkey (Mandatory Prerequisite)

Under Article 18/B, added to Mediation Law No. 6325 on Civil Disputes by Law No. 7445, applying to a mediator has been a procedural requirement in disputes arising from lease relationships in Turkey since 1 September 2023. Accordingly, before a rent determination lawsuit is filed, one of the parties must start the process by applying to the mediation office at the courthouse.

b. Completion of the Mediation Process for Rent Determination in Turkey

In mediation in Turkey, the parties seek a settlement on the rent with the assistance of a mediator. If an agreement is reached at the end of mediation, the settlement document is binding and there is no need to file a rent determination lawsuit; under Article 18/B of the Mediation Law, an enforceability annotation for this document must be obtained from the civil court of peace where the property is located. If the parties cannot agree, the final non-settlement report issued by the mediator makes it possible to file the lawsuit.

c. Competent Court and Venue for a Rent Determination Lawsuit in Turkey

The competent court for a rent determination lawsuit in Turkey is the Civil Court of Peace, which under Article 4(1)(a) CCP hears all disputes arising from lease relationships, including claims for rent receivables. Venue lies with the court of the defendant’s domicile under Article 6 CCP and the court of the place of performance of the contract under Article 10 CCP, which in practice is usually the place where the leased property is located. In practice, the lawsuit is usually filed before the Civil Court of Peace where the property is located because this facilitates expert examination and site inspection.

d. Filing the Lawsuit by Petition to the Court in Turkey

If mediation ends without agreement, the landlord or the tenant may file a rent determination lawsuit by submitting a petition to the competent Civil Court of Peace in Turkey. The final non-settlement report issued by the mediator must be attached to the petition; missing documents may delay the proceedings before the Turkish court and weaken the claimant’s position on comparable rents. The petition should include:

• Information about the parties and the lease agreement,
• The start date and duration of the lease relationship,
• The current rent and payment receipts or bank statements,
• Comparable rental values,
• Details of the property type (e.g., title deed information),
• The new rent requested.

e. Payment of Court Fees and Expenses in Turkey

For the petition to be processed in Turkey, the filing fee, the advance court fee and the advance on costs must be paid. Rent determination lawsuits are subject to a proportional court fee. The following rules apply to fees and costs:

• Basis of the Court Fee: Since the Law on Fees contains no specific rule for these cases, in the practice of the Turkish Court of Cassation the fee is based on the monthly rent difference where a monthly rent is to be determined and on the annual rent difference where an annual rent is to be determined.
• Short Payment of the Fee: If the court fee is paid short, the claimant is given time to complete it; if it is not completed, the file is removed from the docket and, unless renewed in time, the lawsuit is deemed not filed.
• Insufficient Advance on Costs: If the advance on costs is insufficient, a final period of two weeks is granted under Article 120(2) CCP.

How Is the New Rent Determined in a Rent Increase Lawsuit in Turkey?

In a rent determination lawsuit in Turkey, the new rent is set by the judge under the criteria in Article 344 TCO by assessing together the CPI change, the condition of the property, comparable rents and the principle of equity. The judge decides within the statutory limits and according to the specific features of the case; the main criteria considered are as follows.

1. CPI (Consumer Price Index) Change Rate in Turkey

The court first considers the twelve-month average CPI change of the previous lease year in Turkey. By setting a statutory upper limit on rent increases, the CPI rate prevents excessive rent hikes in Turkey and provides a reasonable basis for rent determination. In leases exceeding five years, however, the court is not limited to the CPI and also takes the other criteria into account.

The temporary 25 percent cap that applied under Provisional Articles 1 and 2 TCO to residential lease periods renewed in Turkey between 11.06.2022 and 01.07.2024 expired on 01.07.2024. For lease periods beginning after that date, the twelve-month average CPI change is once again the benchmark.

2. Current Condition of the Leased Property in Turkey

The physical condition, location, age, state of maintenance, manner of use and features of the property in Turkey directly affect the rent. Renovated, centrally located properties with modern features are generally assessed at a higher rent; the expert examination is based on the current condition of the property in the lease period concerned.

3. Market and Comparable Rents in Turkey

The court considers the current rents of similar properties in the area where the property in Turkey is located. Through this comparison, the market rent is identified and a market-appropriate rent is reached in light of comparable data. Lease agreements submitted as comparables must have been concluded in the same period and be comparable in location, size and features.

4. What Does the Expert Do in a Rent Determination Lawsuit in Turkey?

In a rent determination lawsuit in Turkey, the court-appointed expert compares the leased property examined during the site inspection with comparable properties and submits a report on the market rent for the lease period in dispute. The report should contain verifiable explanations of the dates and amounts of the comparable leases, the location and features of the property and the method by which the result was reached.

Under Article 281 CCP, the parties may object to the expert report within two weeks of service and request that deficiencies be remedied, an additional report be obtained or a new expert be appointed. The Turkish court is not bound by the expert report; however, if it relies on the report, it must verify whether the comparables are truly comparable.

5. Principle of Equity in Turkey

The principle of equity in Article 344(3) TCO plays an important role in the judge’s assessment in Turkey. The judge does not apply the market rent found from comparables directly; the judge applies a “long-term tenant discount” in favour of a tenant who has occupied the same property for a long time and, taking into account the general trend of rent increases, strikes a balance between the interests of the parties.

In a rent determination lawsuit in Turkey, the new rent is therefore determined not only by the CPI rate but through a multi-faceted assessment of the property’s features, market rents in the area and the principle of equity. Considering all these criteria together, the court seeks to deliver a balanced decision that protects the interests of both the landlord and the tenant.

How Is the Equity Discount (Long-Term Tenant Discount) Applied in a Rent Determination Lawsuit in Turkey?

In a rent increase lawsuit in Turkey, the judge applies an equitable discount in favour of the long-term tenant to the market rent found from comparable rents; in practice, this is called the “equity discount” or “long-term tenant discount”. The discount is based on the idea that it would be inequitable to subject a tenant who has used the property for a long time to the same rent as a new tenant renting the same property for the first time.

The following points are decisive in applying the equity discount in Turkish practice:

• Criteria for the Discount: When setting the rate of the discount, the judge takes into account the duration of the lease relationship, how far the current rent has moved away from the market rate, the condition of the property and market conditions. The discount is reflected as a reduction in the rent set by the court and is applied by the judge in line with the principle of equity.
• Rate of the Discount: The rate of the equity discount is not specified in Turkish law and may vary in each case. In decisions upheld by the Turkish Court of Cassation, the discount in favour of a long-term tenant is most often applied at 10 percent; however, since the circumstances of each case differ, the judge sets the rate according to the specific case, considering the length of the tenancy and economic conditions together.

How Long Does a Rent Determination Lawsuit Take in Turkey?

Although there is no fixed rule on the duration of a rent increase lawsuit in Turkey, first-instance proceedings are generally concluded within 12 to 18 months in practice. If an appeal is lodged, it may take longer for the decision to become final; the process may also be faster or longer. The main factors affecting the duration are:

• Workload of the Court: The workload of the court directly affects how quickly the file is processed and how often hearings are held. Under the third paragraph added to Article 147 CCP by Law No. 7589, in force since 31.07.2026, the interval between hearings cannot exceed three months, although the judge may set a longer interval with reasons in mandatory cases such as a prolonged expert examination.
• Expert Examination: Since rent determination relies on technical and market data, courts refer the file to an expert. The appointment of the expert, preparation of the report, objections and additional reports can significantly extend the duration.
• Site Inspection and Evidence: A site inspection and the collection of evidence may be needed to assess the condition of the property and comparable rents.
• Appeal (Regional Court of Appeal) Process: A rent determination decision cannot be enforced before it becomes final. If either party appeals the first-instance decision, finality is delayed until the regional court of appeal completes its review.

Seeking advice from an experienced lawyer in Turkey before starting the legal process is important for both time management and preventing loss of rights. In particular, missing the thirty-day deadlines may cause the decision to apply one year later, after lengthy proceedings.

Can a Rent Determination Decision Be Appealed in Turkey?

In Turkey, a rent determination decision can be appealed to the regional court of appeal within two weeks of service (Article 345 CCP) if the value of the case exceeds the finality threshold in Article 341(2) CCP. If the value is below that threshold, the first-instance decision is final and no appeal lies.

An appeal on points of law to the Court of Cassation against the regional court’s decision is limited: under Article 362(1)(b) CCP, in such lease-related cases it is available only if three months’ rent exceeds the cassation threshold, and the time limit is two weeks from service (Article 361 CCP). The appeal and cassation thresholds in Turkey are updated every year by the revaluation rate; under Additional Article 1(2) CCP, the applicable threshold is the amount in force on the date the lawsuit was filed.

What Are the Results of a Rent Determination Lawsuit in Turkey?

The main result of a rent determination lawsuit in Turkey is that the rent payable in the new lease period is set bindingly by court decision. The period from which the decision applies, how the costs are allocated and how the determined difference is collected are also among the results of the lawsuit.

1. Determination of the New Rent in Turkey

The court resets the rent in Turkey by taking into account the features of the property, the rents of similar properties in the area and economic indicators such as the CPI. In line with the principle of equity and Article 344 TCO, care is taken that the rent is neither excessively increased nor kept excessively low.

The new rent becomes the amount the tenant must pay in the relevant lease period and is binding on the parties. In the following lease years, this rent is increased within the CPI cap unless there is a new agreement or determination decision under Turkish law.

2. Retroactive Effect and Period of Application in Turkey

The period from which the rent set in a rent determination lawsuit in Turkey applies depends on whether the time limits and notice requirements in Article 345 TCO have been met. If the lawsuit was filed at least thirty days before the new period, written notice was given to the tenant at least thirty days before the new period, or the contract contains an increase clause, the rent set by the court applies from the beginning of the lease period to which the lawsuit relates.

If none of these conditions is met, the court decision applies only from the following lease period. This is of critical importance for protecting the rights of the parties and ensuring legal certainty in Turkish lease relationships.

3. Which Rent Does the Tenant Pay While a Rent Determination Lawsuit Is Ongoing in Turkey?

While a rent determination lawsuit is ongoing in Turkey, the tenant continues to pay the current rent and, if applicable, the annual increase under the contract or within the CPI cap. The pending lawsuit does not give the tenant the right to stop paying rent or to pay an amount of their own choosing; failure to pay the current rent creates a risk of eviction for default.

Once the determination decision becomes final, the difference between the rent paid and the determined rent can be claimed from the tenant from the period from which the decision applies. In practice in Turkey, it is an important precaution for the tenant to plan payments with the accumulating difference in mind during the proceedings.

4. Allocation of Litigation Costs and Fees in Turkey

A rent determination lawsuit in Turkey is subject to a proportional court fee; the decision fee is charged on the monthly rent difference if a monthly rent is to be determined, and on the annual difference if an annual rent is to be determined. Technical procedures such as expert examination and site inspection are required during the proceedings and give rise to separate costs. At the end of the case, the court allocates the litigation costs to the parties according to the degree to which each party succeeded under Article 326 CCP.

5. Binding Nature and Legal Consequences of the Decision in Turkey

The court’s decision on rent determination in Turkey is subject to review by a higher court if it exceeds the appeal and cassation thresholds. When the time limits for legal remedies expire or the higher court upholds the decision, it becomes final and the new rent is officially determined.

If the tenant does not pay the determined rent after the decision becomes final, the landlord may resort to legal remedies under Turkish law. A rent determination lawsuit cannot be used directly for collection; for the determined difference, separate enforcement proceedings or an action for receivables are needed. For unpaid rent, eviction of the tenant for default may also be requested, provided that proper notice and time are given.

6. Can a Rent Determination Decision Be Enforced Before It Becomes Final in Turkey?

In Turkey, a rent determination decision cannot be enforced before it becomes final as regards the determined rent; even after it becomes final, the determination decision alone is not a basis for judgment-based enforcement. It is also accepted that ancillary items in the decision, such as litigation costs and attorney fees, cannot as a rule be enforced before finality.

After the decision becomes final, the landlord may start enforcement proceedings without a judgment or file an action for the difference; the final determination decision is strong evidence of the existence and amount of the receivable in these proceedings. Under the 24.11.1995 decision of the Grand General Assembly for the Unification of Judgments of the Turkish Court of Cassation, interest runs on the rent difference from the date the determination decision becomes final, without any need for a separate notice.

The Turkish Court of Cassation, Grand General Assembly for the Unification of Judgments, Docket No. 1994/2, Decision No. 1995/2, dated 24.11.1995 resolved the conflict between chambers on the date from which interest runs on the rent difference. The Assembly accepted that where a claim is based on a court decision, the debtor falls into default without notice, and held that interest on the rent difference runs from the date the rent determination decision becomes final. The landlord may therefore claim the difference with interest after finality without sending a separate notice.

7. Resolution of Disputes and Legal Certainty in Turkey

A rent determination lawsuit in Turkey allows rent disputes between the tenant and the landlord to be resolved before the court. The parties thus obtain an objective and lawful determination of the rent. The rent clarified by court decision prevents future disputes and makes the lease relationship healthier and more sustainable.

From Which Date Does a Rent Determination Decision Apply in Turkey?

Under Article 345 TCO, the date from which a rent determination decision takes effect in Turkey depends on when the lawsuit was filed, whether written notice was given to the tenant and whether the contract contains an increase clause. These rules also determine whether the decision can be applied retroactively.

1. If the Lawsuit Was Filed Before the New Lease Period or Timely Notice Was Given in Turkey

If the rent increase lawsuit in Turkey was filed at least thirty days before the new lease period began, or written notice was sent to the tenant at least thirty days before the new period and the lawsuit was filed by the end of that period, the new rent set by the court applies from the beginning of the relevant lease period. If the lease agreement contains an express provision that the rent will be increased in the new period, the decision in a lawsuit filed by the end of the new period also applies from the beginning of the new lease period.

2. If These Conditions Are Not Met in Turkey

If none of these conditions is met in Turkey, the new rent set by the court applies only from the beginning of the following lease period. In this case, the decision takes effect not for the period in which the lawsuit was filed but for the following lease period.

3. Can a Retroactive Rent Determination Lawsuit Be Filed in Turkey?

Under Turkish law, the new rent set in a rent determination lawsuit as a rule applies prospectively; however, if the conditions in Article 345(2) TCO are met, the decision takes effect back to the beginning of the period even if the lawsuit was filed after the new period began. Two different situations are distinguished in practice:

• The Lease Agreement Contains a Rent Increase Clause: If the contract provides that the rent will be increased in the new lease period, the decision in a lawsuit filed by the end of the new period applies from the beginning of that period, which started before the lawsuit was filed.
• The Lease Agreement Contains No Rent Increase Clause: If there is no increase clause, the landlord must file the rent increase lawsuit at least thirty days before the new lease period or give the tenant written notice within that time and exercise the right to sue by the end of the new period. If these conditions are met, the rent ordered by the court applies from the beginning of the new lease period.

Retroactive rent determination in Turkey is possible only as an exception and is strictly subject to form and time requirements. In no case can the decision be applied to periods earlier than the lease period to which the lawsuit relates; rent differences for past periods cannot be claimed.

What Are the Lawyer Fees and Court Costs for a Rent Determination Lawsuit in Turkey?

The cost of a rent determination lawsuit in Turkey consists of the proportional court fee, the advance on costs, expert and site inspection costs and attorney fees, most of which depend on the determined rent difference: the court fee on the monthly or annual difference depending on the claim, and the attorney fee on the annual difference. Before filing, it is important to assess the financial side of the process with a lawyer experienced in rental law in Turkey and to plan the expenses accordingly.

1. How Is the Court Fee Calculated in a Rent Determination Lawsuit in Turkey?

Rent determination lawsuits in Turkey are subject to a proportional court fee. Since the Law on Fees contains no specific provision for rent determination lawsuits, under the practice confirmed by the 3rd Civil Chamber of the Turkish Court of Cassation in its decisions of 25.11.2024 resolving conflicting appellate rulings, the decision fee is charged on the difference between the monthly rent ordered and the monthly rent previously paid where a monthly rent is to be determined; where an annual rent is to be determined, the annual difference is used. An advance fee is collected on the requested difference when the lawsuit is filed, and the decision fee is calculated on the determined difference. Fee rates and fixed fees are set anew each year.

In addition, judicial procedures such as expert examination and on-site inspection are carried out during the proceedings before the Turkish courts. The fees for these procedures are collected from the parties as an advance on costs set by the court at the beginning of the case or at the relevant stage; litigation costs arise under items such as expert fees, site inspection costs, notification costs and file expenses.

2. How Are Attorney Fees Determined in a Rent Determination Lawsuit in Turkey?

If legal assistance is obtained from a lawyer in Turkey, the attorney fee is agreed between the lawyer and the client on the basis of the Minimum Attorney Fee Tariff. This fee may vary depending on the amount in dispute, the legal and technical complexity of the case and the terms of the power of attorney agreement; however, a fee below the minimum set in the tariff cannot be agreed.

The attorney fee awarded against the losing party is calculated proportionally under Article 9 of the Minimum Attorney Fee Tariff on the basis of the annual amount of the difference between the determined rent and the previous rent; this amount cannot be lower than the fixed fee in the tariff. Since the tariff is updated every year in Turkey, the calculation is made according to the tariff in force on the date of the decision.

3. What Does a Tenant Who Loses a Rent Increase Lawsuit Pay in Turkey?

A tenant who loses a rent determination lawsuit in Turkey pays the newly determined rent and the rent difference accumulated from the period to which the decision applies, and is also liable for litigation costs and the opposing party’s attorney fee in proportion to the outcome. If the court has accepted only part of the claim, litigation costs are shared between the parties according to the rate of acceptance and rejection under Article 326 CCP.

If the parties fail to agree at the mediation stage, the mediation fee for the first two hours is paid from the budget of the Ministry of Justice and later included in the litigation costs to be collected from the party that loses the case. For this reason, it is often less costly for a tenant paying a rent clearly below the market rate in Turkey to consider settlement options rather than prolong the proceedings.

Can a Rent Increase Lawsuit Be Filed for Commercial Premises in Turkey?

Under the Turkish Code of Obligations, not only residences but also roofed commercial leases can be the subject of a rent determination lawsuit. A rent determination lawsuit is legally possible for workplace leases of companies in Turkey, merchants and tradesmen established in Turkey under Commercial Law; the law makes no distinction between residences and workplaces in this respect.

The following points stand out for rent determination lawsuits in commercial leases in Turkey:

• Dispute or Below-Market Rent: In commercial leases in Turkey as well, if a dispute arises over the rent or the current rent falls below the market rate, the landlord or the tenant may apply to the court to have the rent reset. In these leases too, a rent increase lawsuit becomes relevant when the rent needs to be updated according to economic conditions, especially in long-term relationships.
• Legal Persons and Tax Obligations: Natural persons and legal persons who are parties to a commercial lease in Turkey may also file a rent determination lawsuit under the TCO to have the rent set according to objective conditions. However, since commercial leases give rise to tax obligations such as Value Added Tax (VAT) and withholding tax, it is important to state clearly in the petition whether the rent to be determined is gross or net and to obtain support from a tax law attorney in Turkey.

Who Can File a Rent Determination Lawsuit in Turkey?

Under Turkish law, a rent determination lawsuit can be filed by the landlord and the tenant who are parties to the lease; in cases such as the landlord’s death, the sale of the property or co-ownership, the persons entitled to sue are determined according to this capacity. The tenant may also file a determination lawsuit by arguing that the rent is above the market rate; although this route is used less often in practice, it is legally possible.

1. Can the Landlord’s Heirs File a Rent Determination Lawsuit in Turkey?

When the landlord dies, the heirs become parties to the lease agreement upon the transfer of inheritance under Turkish inheritance law and are entitled to file a rent determination lawsuit. Since heirs own the estate jointly until partition (Article 640 TCC), they must as a rule file the lawsuit together, join it or ratify it, or act through a representative appointed to the community of heirs by the civil court of peace.

2. Can a New Owner File a Rent Determination Lawsuit in Turkey?

If a rented property is sold to another person in Turkey, the new owner becomes a party to the lease under Article 310 TCO. The new owner is therefore entitled to file a rent determination lawsuit within the framework of the term and procedural provisions of the existing lease; however, the procedures and time limits under the existing contract must be followed meticulously.

The five-year period is calculated not from the date of the transfer of ownership but from the start of the lease relationship under Turkish law, because the new owner has taken over the existing contract. Since the new owner is a party to the lease, they may also exercise rights such as eviction undertakings, rent determination lawsuits and eviction for personal need.

3. How Is a Rent Determination Lawsuit Filed for a Co-Owned Property in Turkey?

According to Turkish Court of Cassation practice, a rent determination lawsuit can be filed not only by the parties to the lease but also by the owner of the property or each of its co-owners. The persons entitled to sue are determined according to the type of ownership:

• Co-Ownership by Shares: If the leased property is held in co-ownership by shares, each co-owner may request the determination of the rent in proportion to their own share, since under Article 688(3) of the Turkish Civil Code (TCC) each co-owner has an owner’s rights regarding their share; for a determination of the entire rent, the co-owners who are landlords must join the lawsuit together.
• Joint Ownership: If the property is held in joint ownership (for example, as part of an undivided estate), the lawsuit can proceed only if all heirs file it together, join the lawsuit or ratify it, or through a representative appointed to the community of heirs. It should therefore be checked in the land registry before filing whether ownership is by shares or joint.

In Turkish Court of Cassation, 3rd Civil Chamber, Docket No. 2010/6544, Decision No. 2010/11768, dated 01.07.2010, the lease named a company as landlord while the claimants were co-owners of the property, and the dismissal of their claim for lack of the landlord’s capacity was reversed. The Chamber expressly stated that a rent determination lawsuit can be filed not only by the parties to the lease but also by the owner or each co-owner, that in co-ownership by shares each co-owner may seek a determination in proportion to their share, and that in joint ownership all heirs must act together or a representative must be appointed to the community of heirs.

Can a Rent Determination Lawsuit Be Filed While an Eviction Lawsuit Is Ongoing in Turkey?

Under Turkish law, it is possible to file a rent determination lawsuit while an eviction lawsuit is pending, and this is a common situation in practice. Disputes between tenants and landlords often involve both the determination of the rent and the eviction of the property.

In Turkish law, an eviction lawsuit and a rent determination lawsuit are separate actions serving different purposes:

• Eviction Lawsuit: Seeks the vacation of the property.
• Rent Determination Lawsuit: Seeks to reset the rent according to market conditions.

The 3rd Civil Chamber of the Turkish Court of Cassation has held that, where a rent determination lawsuit is filed while an action for annulment of objection and eviction is pending, the subject matter and cause of the two cases are different and there is therefore no lis pendens (Turkish Court of Cassation, 3rd Civil Chamber, Docket No. 2010/2805, Decision No. 2010/4036, dated 11.03.2010). In that case, the first-instance court had dismissed the rent determination lawsuit because an action for annulment of objection and eviction concerning the same period was pending; the Chamber reversed the decision, noting that the first case sought collection of underpaid rent and eviction, while the second sought determination of the annual rent.

When the eviction lawsuit is accepted and the decision becomes final, ending the lease relationship, the rent determination lawsuit can only produce results for the periods during which the lease continued. The parties in Turkey should therefore obtain legal support and conduct both proceedings carefully so as not to lose their rights regarding either the eviction or the rent.

Can a Rent Determination Lawsuit Be Filed for Oral Lease Agreements in Turkey?

Since the Turkish Code of Obligations does not subject lease agreements to a form requirement, oral leases are also valid and a rent determination lawsuit can be filed in an oral lease relationship in Turkey. As long as the existence of the oral lease is acknowledged or proven, a lawsuit for rent determination can be filed.

The main difficulty with oral leases in Turkey arises at the evidence stage. The start date of the lease relationship, the rent and whether there is an increase clause are decisive for calculating the five-year period and the period from which the decision applies. The following evidence therefore becomes important:

• Bank statements,
• Witness statements,
• Correspondence,
• Utility subscription records.

If the parties to an oral lease later sign a contract to put the existing relationship in writing, this alone does not restart the five-year period under Turkish law; if the rent in the new contract does not reflect the market rate at that time, the time elapsed since the start of the original lease is taken into account. It is very important for the parties to document the situation and present sufficient evidence so that the court can reach an equitable decision.

Can Foreigners File a Rent Determination Lawsuit in Turkey?

In a lease relationship concerning property located in Turkey, foreigners may file a rent determination lawsuit before Turkish courts or be defendants in such a lawsuit, regardless of the nationality of the parties. Although questions of applicable law and competent court arise in leases with a foreign element, the rights and obligations of foreign natural and legal persons in this respect are clearly regulated under Turkish law.

Two basic rules apply in this respect under Turkish law:

• Applicable Law: Under Article 25 of Law No. 5718 on International Private and Procedural Law (IPPL), contracts relating to immovable property or its use are subject to the law of the country where the property is located. Accordingly, Turkish law applies to leases of property located in Turkey regardless of the parties’ nationality, and the TCO provisions on rent determination are applied.
• International Jurisdiction: The international jurisdiction of Turkish courts is determined under Article 40 IPPL according to the domestic rules on venue.

In this context, a foreign lessor who owns immovable property in Turkey or a foreigner who is a tenant in Turkey may file a rent determination lawsuit under the relevant TCO provisions to have the rent reset. In practice, not only foreign natural persons but also foreign companies’ branches and liaison offices in Turkey are frequently involved in property lease relationships.

Without any distinction based on nationality, the TCO provisions on rent determination apply to all determination claims arising from leases of property located in Turkey. Foreigners have full capacity to sue in this respect; parties living abroad can pursue the lawsuit through a litigation lawyer in Turkey and can also take part in the mandatory mediation process through a representative.