How loan payments are calculated
- Your monthly payment is calculated using the standard amortization formula, based on the loan amount, monthly interest rate and number of payments.
- The payment amount stays fixed for the entire loan term — only the interest/principal split changes each month.
- A longer loan term lowers your monthly payment but increases the total interest you pay overall.
The amortization formula
Monthly payment = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the loan principal, r is the monthly interest rate (annual rate ÷ 12), and n is the total number of monthly payments.
For example, a €20,000 loan at 6.5% APR over 5 years (60 payments) results in a monthly payment of roughly €392, with about €3,528 in total interest paid over the life of the loan.