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Mortgage overpayment calculator with a one-off lump sum option

Most calculators only handle a monthly overpayment. This one has a dedicated one-off lump sum field — drop in a bonus, inheritance, ISA maturity or savings pot and see exactly how much time and interest it knocks off your UK mortgage.

Your mortgage

UK calculator
Estimated monthly payment£1,254
Your overpayment result

You'll be mortgage-free 6 years 9 months earlier
and save £46,940 in interest.

New payoff
September 2044
was June 2051
Total interest
£109,338
was £156,277

Balance over time

Without overpaying With overpaying
WithoutWith overpay
Term25 years18 years 3 months
Total interest£156,277£109,338
You save£46,940 · 6y 9m

Want to clear it even faster?

A lower interest rate could save you thousands more on top. See if you could remortgage to a better deal.

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We may receive a commission if you remortgage through a partner broker. This never affects the rate you're offered.

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