Free financial calculator

Interest-Only Mortgage Overpayment Calculator

See how overpaying capital could change an interest-only mortgage without confusing it with a repayment mortgage.

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Adjust the assumptions

Interest-Only Mortgage Overpayment Calculator

See how overpaying capital could change an interest-only mortgage without confusing it with a repayment mortgage.

Figures are estimates. You can adjust every assumption.

Result

£0

View year-by-year breakdown +
YearContributionsGrowthBalance

Questions answered

What this calculator helps you work out

  • How much interest could an interest-only mortgage overpayment save?
  • How would a lump sum change the monthly interest payment?
  • How much capital could remain at the end of the term?

Common questions

Interest-Only Mortgage Overpayment Calculator FAQs

Does the normal interest-only payment reduce the mortgage balance?+

Usually no. It covers interest, so a separate repayment plan or capital payment is still needed.

Will my monthly payment fall after an overpayment?+

It may if the lender recalculates interest on the lower balance, but timing and lender policy vary.

Can I clear the mortgage through monthly overpayments?+

Potentially, if enough capital is paid before the term ends and the lender permits it. The calculator estimates the remaining balance.

Go beyond the result

Can You Overpay an Interest-Only Mortgage?

See a worked example, the trade-offs to consider and the assumptions that can change the answer.

Read the guide →