One of the issues that most closely concerns both property owners and tenants in the real estate sector is the official rent increase rates announced at the beginning of each month. As of May 2026, the legal upper limit for lease agreements to be renewed has been formalized together with the inflation data announced by the Turkish Statistical Institute (TURKSTAT). So, what is the maximum increase tenants whose contracts will be renewed this month may face? How much of an increase can landlords legally request? We have taken a closer look at the current situation in workplaces and residences, together with calculation examples.

What Is the Official Rent Increase Rate for May 2026?

In accordance with the regulations made in the Code of Obligations (following the end of the previous 25% residential cap practice), the legal upper limit for rent increases in both residential and workplace leases is calculated based on the 12-month CPI (Consumer Price Index) average.

According to the data announced by TURKSTAT, the maximum increase rate of 55.20% (representative current inflation path rate) has been determined for lease agreements to be renewed in the May 2026 period.

Important Note: This rate represents the highest increase limit that landlords can apply. The property owner and the tenant may mutually agree on an increase amount below this rate; however, unless there is a legal obligation, an increase above this rate cannot be requested.

Step-by-Step Rent Increase Calculation Example

To help a tenant renewing their contract in May see the new amount more clearly, let’s do a simple calculation together:

• Current Rent Amount: 20.000 TL
• Rent Increase Month: May 2026
• Legal Cap Increase Rate: 55.20%
• Maximum Increase Amount: 11.040 TL
• New Term Monthly Rent Amount: 31.040 TL

3 Critical Rules Tenants and Landlords Should Know

To avoid disputes between the parties during lease renewal periods, it is necessary to know the legal framework well:

1. “Rent Determination” in Contracts That Have Completed 5 Years

If your tenancy relationship in the same property has completed 5 years, the landlord is not required to rely solely on the 12-month CPI average. Taking comparable (market) rents in the area into consideration, the property owner may file a “Rent Determination Lawsuit” and request that the rent be aligned with the market value.

2. Is the Rate Written in the Contract Valid?

If your lease agreement includes a clear clause that is lower than CPI, such as “The rent increase will be applied at a rate of 30% each year,” this rate, which is in favor of the tenant, is valid. However, if the rate written in the contract is above the legal cap of 55.20%, the tenant has the right to request that it be reduced to the legal limit.

3. Has the Situation Changed for Workplaces?

No, as has long been the case, the 12-month CPI average rule continues to apply in workplace (roofed workplace) leases. In other words, for businesses that will renew shop, office, or store agreements in May 2026, the upper limit is also 55.20%.