Maximum Interest Rate Check
Checks whether the interest agreed when lending or borrowing money exceeds the maximum rate allowed by law. Interest deducted in advance and fees are counted as interest.
Any money received in return for the loan counts as interest, even if it is called a fee, a thank-you payment or a discount (Interest Limitation Act, Article 4).
Leave blank if there was none. If interest was deducted in advance, the amount actually received is treated as the principal (Interest Limitation Act, Article 3).
The maximum rate is determined as of the time the interest was agreed.
Frequently asked questions
- What is the legal maximum interest rate?
- For contracts made on or after July 7, 2021, the maximum rate is 20% a year under both the Interest Limitation Act and the Act on the Registration of Credit Business and Protection of Finance Users; for contracts made from February 8, 2018 to July 6, 2021, it is 24% a year. The maximum rate is set by the date the interest was agreed (the contract date).
- Can I get back interest I already paid above the maximum rate?
- Interest above the maximum rate has no effect, and if it has already been paid, it can be counted as repayment of the principal, or you can ask for it to be returned (Interest Limitation Act, Article 2(3) and (4); Act on the Registration of Credit Business and Protection of Finance Users, Article 8(4) and (5)). Receiving interest above the maximum rate can also be subject to criminal punishment (Interest Limitation Act, Article 8; Act on the Registration of Credit Business and Protection of Finance Users, Article 19).
- Do interest deducted in advance and fees count as interest?
- Any money received in return for the loan counts as interest, even if it is called a fee, a thank-you payment or a discount (Interest Limitation Act, Article 4). If interest was deducted in advance, the amount actually received is treated as the principal (Interest Limitation Act, Article 3).
- Do I have to pay interest on a loan from an unregistered (illegal) lender?
- A loan contract made on or after July 22, 2025 with an unregistered lender has no effect as to any of the interest agreed (Act on the Registration of Credit Business and Protection of Finance Users, Article 11(1)). For contracts made before that date, interest above the maximum rate has no effect.
This is a reference calculation based on the maximum rate at the time of the contract. Late-payment interest, partial repayment or an extension of the contract can change the result. To get back interest you have already paid, or to have it deducted from the principal, talk to a lawyer.
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