Interest calculator

How is it calculated?

Statutory interest (yasal faiz) is the interest that applies when no rate has been agreed in the contract. From 31 July 2026, under the amended art. 1 of the Interest Law, the rate is 80% of the rediscount rate applied by the Central Bank (TCMB) on 31 December of the previous year. If the rediscount rate on 30 June differs by five percentage points or more from the 31 December rate, 80% of the 30 June rate applies in the second half of the year. Before that date, annual rates of 9% (1 January 2006 – 31 May 2024) and 24% (1 June 2024 – 30 July 2026) applied.

Commercial default interest: in commercial matters, the rate the Central Bank applies to short-term advance transactions may be claimed even without a contractual provision (Interest Law art. 2(2)). Under the law, the rate on 31 December of the previous year is used; if the rate on 30 June differs by five percentage points or more, the new rate applies in the second half of the year. Because some practitioners calculate advance interest according to the dates on which the Central Bank changed its rate, that method can also be selected.

Simple interest is used; no interest may be charged on interest for statutory or default interest (Interest Law art. 3). A year is taken as 365 days, and the number of days is the difference between the start date and the calculation date.

Note: The results are for general information. The date from which interest runs (date of default, lawsuit or enforcement proceedings), the type of interest that applies and any partial payments depend on the particular case. The rates were last checked against the Central Bank and Official Gazette sources on 1 October 2026.