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See how fast you could be mortgage-free.

Find out exactly how many years and how much interest you'd save by overpaying your UK mortgage. Updates instantly as you type.

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.

Check remortgage rates

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

Compound effect, in reverse

Mortgage interest compounds against you. Every overpayment shrinks the balance interest is charged on — so the saving snowballs over the years.

Standard amortisation maths

We run a full month-by-month schedule with and without your overpayments, then show you the gap. Same approach your lender uses.

Watch the 10% cap

Most UK lenders cap fee-free overpayments at 10% of the balance per year on a fix. Toggle 'Advanced' to model your lender's limit.

Common questions

Quick answers about overpaying a UK mortgage.

Other ways to use the calculator

Same maths, different framing — see how much you'd save by paying off your mortgage early, with a lump sum, or simply sooner than the contracted term.

Should you overpay? Honest guides

Straight answers to the questions UK homeowners actually ask before overpaying.

Lender-specific calculators

Same calculator, tailored guidance for your lender's overpayment rules and limits — Halifax, Nationwide, Santander, NatWest, Barclays, HSBC, Lloyds, TSB and Virgin Money.

Which UK lender lets you overpay the most?

Side-by-side comparison of overpayment caps, ERCs and reset windows for all 9 major UK lenders.

See the comparison →