October 2026 Rent Increase Rate: 31.49% — How Is the New Rent Calculated?

How Is the October 2026 Rent Increase Calculated?

The October 2026 rent increase is calculated by multiplying the current rent by 31.49% and adding the resulting increase to the current rent. Under Article 344 of the Turkish Code of Obligations, the 12-month average CPI is the legal upper limit; the parties may freely agree to a lower increase.

With TurkStat’s announcement of the September 2026 inflation figures, the legal increase limit for leases renewed in October was confirmed. In September, the consumer price index rose by 1.84% month on month and 29.73% year on year, while the change in the 12-month average CPI used as the basis for rent increases was 31.49%.

The calculation formula is: New Rent = Current Rent + (Current Rent x 0.3149). If the lease specifies a lower rate, that rate applies; however, the legal cap of 31.49% cannot be exceeded.

October 2026 Increase Calculation Table for Different Rent Amounts

Applying the October 2026 rent increase cap of 31.49% raises a rent of 20,000 TL to 26,298 TL, 30,000 TL to 39,447 TL, 40,000 TL to 52,596 TL, and 50,000 TL to 65,745 TL. The property owner cannot unilaterally demand an increase above these amounts.

Writing “October rent payment” in the bank transfer description helps prevent disputes in advance.

Who and Which Properties Does the October Rent Increase Cap Cover?

The legal increase limit of 31.49% applies only to residential and roofed commercial premises whose lease commencement anniversary falls in October 2026. Tenants whose renewal date falls in another month of the year cannot be charged an interim or additional increase in October.

By law, rent may be increased once a year on the anniversary of the lease commencement date. Following the removal of the 25% limit, the sole benchmark for residential and commercial premises is the 12-month average CPI.

The Downward Trend in Rent Increase Rates: Expectations for the End of 2026

The rent increase cap fell from 32.43% in May to 31.49% in October, recording an uninterrupted decline over the last five months. Annual consumer inflation falling to 29.73%, below the 30% threshold for the first time since November 2021, confirms that the decline in the rent cap will continue in the coming months.

Official figures show the following disinflation path for 2026: May 32.43%, June 32.24%, July 32.03%, August 31.90%, September 31.79%, and October 31.49%. The 30-basis-point decline in the latest month shows that the downward trend has gained momentum.

Central Bank of the Republic of Türkiye projections anticipate year-end inflation in the 26–29% range. This outlook indicates that the rent cap will continue to fall gradually in November and December.

October 2026 Rental Housing Market Dynamics in Kadıköy and on Bağdat Avenue

In the rental housing market in Kadıköy and on Bağdat Avenue, increases for existing tenants remain subject to the 31.49% cap, while rents for newly let vacant flats are rising faster than overall inflation because of limited supply and extensive urban redevelopment. Demand for high-quality new homes along the Suadiye and Caddebostan waterfront remains strong.

The legal cap applies to ongoing leases along Bağdat Avenue, while prices for vacated buildings are set by the free market. Owners seeking temporary accommodation during urban redevelopment are reducing supply, and demand is concentrated on buildings with parking in Suadiye, Caddebostan, Erenköy and Fenerbahçe.

According to Central Bank of the Republic of Türkiye data, increases in new rental prices in Istanbul exceed the national average. Well-priced, high-quality properties in the area are let quickly.

The Essential October 2026 Checklist for Landlords and Tenants

Parties renewing a lease in October should first confirm the lease commencement date, agree on an amount that does not exceed TurkStat’s 31.49% cap, and record the new rent in a signed written agreement. All rent payments must be made through a bank, with a clear payment description, as required by law.

Lease renewal steps:
1. Confirm the Date: Verify that the lease commencement date falls in October.
2. Calculate the Cap: Know that the maximum rate is 31.49% and calculate it correctly.
3. Review the Lease: Check whether the lease provides for a more favourable rate below CPI.
4. Written Agreement: Record the new rent in a signed written agreement.
5. Bank Transfer Description: Write “October rent payment” in the payment description.
6. The 5-Year Rule: Seek expert advice for leases exceeding 5 years.

Frequently Asked Questions (FAQ)