Extra Repayment Calculator
Calculate how much interest and time a one-time extra repayment could save on an existing loan.
Calculate now
Use this extra repayment calculator to compare an existing loan with and without a one-time additional payment. It shows how remaining term, interest cost and total repayment may change.
Extra Repayment Calculator:
Use the result as decision support, not as individual advice. For finance topics, scenarios, total cost, risk, term and personal affordability matter.
How to use the result better
- Calculate conservative, realistic and optimistic cases.
- Look beyond monthly values to total cost or final value.
- Keep safety buffers before making a decision.
Common mistake
One attractive figure can mislead when fees, taxes, rate changes, volatility or long terms are ignored.
Best next step
Compare related financial calculators next. Rate, term, return, inflation and available income are especially useful together.
Is this financial advice?
No. It is an orientation tool and does not replace individual financial, tax or investment advice.
Why are scenarios so important?
Small changes in interest, return, term or costs can change the result significantly.
Next steps
Useful calculators to continue
After the result, related calculators help you understand costs, alternatives and next steps more clearly.
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How to use the result well
Compare several scenarios: Change the key values and check how much the result changes.
Use related calculators: Decisions often become clearer when you also calculate costs, timeframes or alternatives.
How the result is calculated
Monthly interest rate = annual interest rate ÷ 12
Remaining debt after extra repayment = current remaining debt − extra repayment
For each month: interest part = remaining debt × monthly interest rate
Principal part = monthly payment − interest part
New remaining debt = old remaining debt − principal part
Interest saved = interest without extra repayment − interest with extra repayment
Worked example
Example: With €20,000 remaining debt, 6.5% annual interest, a €390 monthly payment and a €3,000 extra repayment, the balance drops immediately. This reduces future interest and can shorten the loan term.
When is an extra repayment worthwhile?
An extra repayment can be attractive when the loan rate is higher than the safe return you could earn elsewhere. The higher the interest rate and the longer the remaining term, the more noticeable the effect can be.
Why does an extra repayment reduce interest?
Interest is calculated on the outstanding balance. When an extra repayment lowers that balance, less interest accrues in later months and more of each regular payment goes toward principal.
What should you check first?
Check whether your contract allows extra repayments, whether limits apply and whether fees or early repayment charges are possible. This calculator shows the mathematical effect, but it does not replace checking the loan contract.
Frequently asked questions
What is an extra repayment?
An extra repayment is an additional payment on top of the regular monthly payment. It reduces the outstanding balance and can reduce both interest cost and remaining term.
Does every extra repayment save money?
Mathematically, it usually reduces interest if there are no additional charges. Whether it is the best choice also depends on the contract, fees and alternative uses of the money.
Why does the calculator ask for the current monthly payment?
The monthly payment determines how quickly the loan is repaid with and without the extra payment. The comparison assumes the regular payment stays the same.
Are the results binding?
No. The results are for guidance only. Your bank's calculation and your loan contract are what matter legally and financially.