The calculation of loan interest is different for different repayment methods. At present, the most common repayment methods are mainly divided into four types: matching principal and interest, average capital, paying interest first, and paying principal and interest at one time. The calculation methods of interest in different ways are as follows.
1. One-time repayment of principal and interest: loan amount * loan interest rate * loan term, in which the general interest rate is annual interest rate and the term is calculated on an annual basis;
2. Interest before principal: loan amount * loan interest rate * loan term. This repayment method is generally monthly, so the general interest rate is monthly, and the loan term is calculated monthly.
3. Matching principal and interest: The repayment method of matching principal and interest means that the repayment amount of each installment is the same, and its calculation formula is also the most responsible, that is, [loan principal × monthly interest rate ×( 1+ monthly interest rate) repayment months ]≤[( 1+ monthly interest rate) repayment months-1].
4. Average capital: Average capital refers to the same monthly repayment principal, and its calculation formula is (loan amount-paid amount) * loan interest rate, where the interest rate is generally the corresponding monthly interest rate.
Bank interest rates are divided into annual interest rate, monthly interest rate and daily interest rate, which are converted as follows:
Daily interest rate (0/000)= annual interest rate (%)÷360= monthly interest rate (‰)÷30.
Monthly interest rate (‰) = annual interest rate (%)÷ 12
When calculating loan interest, banks can use product interest method and transaction interest method:
Product interest method: Accumulate the account balance daily according to the actual number of days, and multiply the accumulated products by the daily interest rate to calculate interest.
Interest = cumulative interest-bearing product × daily interest rate, where cumulative interest-bearing product = total daily balance.
Transaction-by-transaction interest calculation method: calculate interest one by one according to the preset interest calculation formula: interest = principal × interest rate × loan term, with three details:
1. If the interest period is a whole year (month), the interest formula is:
Interest = principal × year (month )× year (month) interest rate
2. If the interest-bearing period is a whole year (month) and days, the interest-bearing formula is:
Interest = principal × year (month )× year (month) interest rate+principal × odd days × daily interest rate.
3. Calculate the interest according to the actual number of days, that is, 365 days per year (366 days in leap year), and each month is the actual number of days in the Gregorian calendar of the current month. The interest calculation formula is:
Interest = principal × actual days × daily interest rate
Banks have the right to freely choose the above three calculation methods, and the parties and financial institutions can agree on this in the contract.
Legal basis:
Provisions of the Supreme People's Court on Several Issues Concerning the Application of Law in the Trial of Private Lending Cases
Article 25 If the lender requests the borrower to pay interest at the interest rate agreed in the contract, the people's court shall support it, except that the interest rate agreed by both parties exceeds four times the market quotation of one-year loan at the time of the establishment of the contract.
The "one-year loan market quotation" mentioned in the preceding paragraph refers to the one-year loan market quotation issued monthly by the National Interbank Funding Center authorized by the People's Bank of China from August 20th, 20th, 20th19th.
Article 27 After the borrower and the borrower settle the loan principal and interest in the early stage, the interest shall be included in the loan principal in the later stage, and the creditor's rights certificate shall be reissued. If the interest rate in the early stage does not exceed four times the market quotation of the one-year loan when the contract is established, the amount specified in the reissued creditor's rights certificate can be confirmed as the loan principal in the later stage. The overcharged interest shall not be used as the loan principal in the future.
According to the calculation in the preceding paragraph, if the sum of the principal and interest that the borrower should pay after the expiration of the loan term exceeds the sum of the interest of the whole loan term based on the initial loan principal and calculated according to the market quotation of the one-year loan at the time of the establishment of the contract, the people's court will not support it.