Interest-only mortgage calculator UK
Estimate monthly interest-only mortgage payments and total interest over the term. See the capital balance still due at the end, excluding fees and rate changes.
Enter your figures
Monthly interest-only payment
Inputs changed. Select Calculate result to update your estimate.
Fixed-rate illustration with interest paid monthly and no capital repaid. Excludes fees and rate changes. The full balance remains payable at the end.
How the interest-only mortgage calculator uk works
Monthly interest = balance × annual rate ÷ 1200. Total interest = monthly interest × term in months.
Data basis: mathematical formula using your inputs. Example prices and rates are illustrative, not current market quotes.
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Worked example: interest-only mortgage
This illustration uses the calculator’s example inputs. It is not a quote or a recommended financial decision.
- Mortgage balance (£)
- 200,000
- Nominal annual interest (%)
- 4.5
- Years
- 25
Monthly interest-only payment: £750.00
Monthly interest = balance × annual rate ÷ 1200. Total interest = monthly interest × term in months.
Interest-only mortgage: questions answered
Will an interest-only payment repay the mortgage balance?
No. The model pays interest only. Unless you repay capital separately, the full original balance remains due at the end of the mortgage term.
Using your result
Example inputs are a starting point. Replace them with your figures and select Calculate result. Results are rounded for display; calculations use unrounded values.
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