UK Mortgage Calculator

Estimate a repayment or interest-only mortgage using the property price, deposit, fixed interest rate and term. The calculator shows the opening loan, loan-to-value, required monthly payment, interest and total mortgage payments.

Mortgage overpayment comparison

Add a planned monthly overpayment to compare the required payment with the planned payment. Results include the revised payoff time, interest, total mortgage payments, final partial payment and estimated time and interest saved. Check any lender overpayment limit and early repayment charge first.

Fees, higher rates and yearly balances

A mortgage product or arrangement fee can be treated as paid upfront or added to the mortgage. An optional higher-rate comparison shows how the required monthly payment could change. The year-by-year amortisation table provides exact payments, interest, capital repaid and closing balances.

Staged rate scenarios

Optionally enter an initial interest rate period in whole years and a follow-on rate. At the transition, the calculator uses the remaining balance and term to recalculate the required monthly payment. This is a user-entered scenario, not a forecast of a lender's future rate. A monthly overpayment stays the same cash amount before and after the transition.

Compare rate and term scenarios

Compare up to three simple rate and term scenarios based on the current opening mortgage balance and repayment type. These comparisons exclude staged rates, voluntary overpayments and the separate stress rate. The form, theme and scenarios are saved only in this browser or app, with no account or cloud sync. Use Clear saved data to remove them and restore defaults. A summary is copied to your device clipboard only when you choose the copy action; copied output is not saved by the app.

Interest-only mortgages

Interest-only payments do not repay the capital. The calculator therefore shows the full capital still due at the end of the term separately and does not present that capital as a repayment-strategy cost.

Assumptions: a single rate stays fixed for the full term; staged rates use only the two rates and transition period entered. Results are scenarios, not forecasts, affordability checks, mortgage offers or financial advice. Mortgage fees are included only as selected. Stamp duty, legal, survey, insurance and other purchase costs are excluded.

Calculations run on your device. Read the privacy notice for hosting, PWA cache and clipboard details.