Mortgage repayment calculator
A mortgage repayment calculator turns three numbers, the loan, the interest rate and the term, into a monthly payment. On a repayment mortgage that payment covers interest and clears the balance by the end of the term. On interest-only it covers just the interest and the full balance is still owed at the end. This free tool shows the monthly cost, the total paid and the total interest, so you can see what a rate really costs over time.
Work out your monthly payment
Free. No email needed. Runs in your browser, stores nothing.
Monthly payment
Total paid
Total interest
Simplified illustration at the rate you entered, assumed fixed for the whole term. Real deals change rate when the initial period ends. Not a quote and not advice. A regulated broker can confirm the real figures for your case.
How to read the result
The monthly payment is what you would pay each month at that rate. On a repayment mortgage the total paid is that payment across the whole term, and the total interest is the part of it that is not clearing your balance. Interest-only shows a lower monthly cost, but remember the full loan is still owed at the end, so it is not a true like-for-like with repayment. Try a slightly higher rate to see how much a future rate rise could add, which is the sort of thing a lender stress tests. To start from a monthly budget instead of a loan, use how much mortgage can I afford. See how much can I borrow and the Bank of England base rate.
Common questions
How is the monthly payment worked out?
For a repayment mortgage it uses the standard amortisation formula: the loan, the monthly interest rate and the number of months combine into a level monthly payment that clears the balance by the end of the term. For interest-only it simply charges the interest on the full balance each month, so the balance itself is not reduced.
Is this a quote?
No. It is an illustration at the rate you type in. Your actual rate depends on the lender, the product, your loan-to-value and your circumstances. It also assumes the rate stays fixed for the whole term, which real deals do not. Treat it as a guide, then let a regulated broker confirm the real figures.
What is the difference between repayment and interest-only?
On repayment you pay interest and chip away at the balance, so the debt is gone at the end of the term. On interest-only you pay only the interest, the monthly cost is lower, but the full balance is still owed at the end and you need a separate plan to repay it. Most residential mortgages are repayment.
Why does a small rate change move the payment so much?
Because the rate applies to the whole balance for the whole term. On a large loan over 25 or 30 years, even half a percent adds up to a meaningful monthly difference and a large difference in total interest. This is why the rate, and matching to the right lender, matters.
Founder, MortgageExplained
Adam spent over eight years as a mortgage adviser at Just Mortgages, with further experience in commercial finance. He is CeMAP and CF qualified. He built MortgageExplained to do one thing well: explain mortgages in plain English, so you know where you stand before you speak to a regulated broker. Every page on the site is written by Adam.
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