Mortgage repayment calculator
Enter the loan, rate and term to see the monthly repayment, the total interest, and what you'll still owe when a fixed deal ends.
Rates checked 3 November 2026 Checked by Daniil Shumko, editor
Monthly repayment
| After | Still owed | Paid off |
|---|---|---|
| 2 years | £191,541 | £8,459 |
| 5 years | £177,160 | £22,840 |
| 10 years | £147,849 | £52,151 |
The formula
Monthly payment = loan × r ÷ (1 − (1 + r)−n), where r is the yearly rate divided by 12 and n is the number of monthly payments. On £200,000 at 5% over 25 years, r is 0.004167 and n is 300, which gives £1,169 a month.
This is for illustration. It assumes the same rate for the whole term and doesn't include arrangement fees, which you can either pay upfront or add to the loan. It isn't a mortgage offer or advice, and we don't recommend lenders.
Common questions
How are mortgage repayments calculated?
A repayment mortgage uses a fixed formula so that equal monthly payments clear the loan and its interest by the end of the term. Early payments are mostly interest; later ones are mostly capital.
How much is a £200,000 mortgage a month?
At 5% over 25 years, about £1,169 a month. At 4% it's about £1,056, and at 6% about £1,289.
What happens when my fixed rate ends?
You move to the lender's standard variable rate unless you remortgage or switch to a new deal. Most lenders let you lock in a new rate up to six months early, so start looking well before the end date.
Sources
This calculator gives a general figure, not tax, legal or financial advice. Where the government publishes worked examples, we test it against them. Found a problem? Tell us.
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