Statutory Interest Calculator
Enter the principal and date range; simple interest is calculated period by period, applying every rate change (Law No. 3095).
Parameters last updated: 9 July 2026
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What are statutory and advance interest in Turkish law?
Under Article 1 of Law No. 3095, statutory (legal) interest applies where interest is owed but no rate was agreed by contract. It has been 24% per year since 1 June 2024 (Presidential Decree No. 8485); before that it was 9% from 1 January 2006. In commercial matters, the creditor may instead claim default interest at the Central Bank's short-term advance rate (Article 2/2), which is 39.75% for 2026.
How is the interest calculated?
The calculation uses simple interest: principal × annual rate × days / 36,500. The date range is split at every rate change, each segment is computed at its own rate and the results are added up. Compound interest is prohibited by Article 3 of Law No. 3095. The start day does not accrue interest; the end day is included. For commercial advance interest, the period rule of Article 2/2 applies: the rate in force on 31 December of the previous year governs the whole year, unless the 30 June rate differs by five points or more, in which case it applies in the second half.
The Constitutional Court annulment effective 1 September 2026
With decision E.2024/24, K.2025/164 (22 July 2025, published 1 December 2025), the Turkish Constitutional Court annulled the statutory interest rate in Article 1 with respect to non-contractual obligations, effective 1 September 2026. A replacement model (80% of the Central Bank rediscount rate) is pending in Parliament as part of the 12th Judicial Package. Check the current legislation for calculations extending beyond that date.
Frequently Asked Questions
What is the statutory interest rate in Turkey in 2026?
It is 24% per year, in force since 1 June 2024 under Presidential Decree No. 8485. From 1 January 2006 to 31 May 2024 the rate was 9%.
What is the advance (commercial default) interest rate for 2026?
It is 39.75% per year, based on the Central Bank communiqué of 20 December 2025; under the period rule of Article 2/2 of Law No. 3095, it applies for all of 2026.
Is compound interest allowed?
No. Article 3 of Law No. 3095 prohibits compound interest on statutory and default interest, subject only to the exceptions reserved by the Turkish Commercial Code.
Which rate applies to late payments in the supply of goods and services?
Under Article 1530/7 of the Turkish Commercial Code, the rate announced by the Central Bank each January applies if no contractual rate exists: 43.00% for 2026, plus a minimum recovery cost of TRY 2,020.
Does the Constitutional Court decision affect calculations?
The annulment of the Article 1 rate for non-contractual debts takes effect on 1 September 2026, and the replacement legislation is still pending. Verify the current rules for calculations extending beyond that date.