OverpayWise

Mortgage intelligence

Free mortgage overpayment calculator

See how extra payments change your mortgage payoff date.

Estimate interest savings, time saved, and your balance over time when you add a regular monthly overpayment.

No account needed

Runs in your browser

Built for quick comparisons

Example scenario

£38,458

Estimated interest saved with a £200 monthly overpayment on the default mortgage.

Inputs

Mortgage details

Private

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Try a scenario

Estimate

Results

Estimated interest saved

£38,458

Estimated time saved

5 years 1 months

Current payment

£1,390

With overpayment

£1,590

+£200/month

Current term

25 years

New term

19y 11m

Assumes the rate stays the same and every overpayment reduces the balance immediately.

Projection

Mortgage balance over time

Original mortgageWith overpayments

Assumptions to review

Interest rate stays fixed

The estimate assumes the same annual rate for the whole remaining term.

Overpayments reduce balance immediately

Some lenders apply payments differently, so check how your provider handles extra payments.

Fees and limits are not included

Early repayment charges, product fees, and annual overpayment caps can change the decision.

What this estimate suggests

Use the result as a comparison point, then check overpayment limits, cash buffer, and whether remortgaging could change the trade-off.

Useful next steps

Important disclaimer

This calculator provides estimates only and does not constitute financial advice. Mortgage calculations may vary depending on lender terms, overpayment limits, interest rate changes, fees, and repayment structures. Always consult a qualified financial advisor or your mortgage provider before making financial decisions.

Learn the basics

How mortgage overpayments work

Mortgage overpayments are additional payments made on top of your standard monthly mortgage repayment. By reducing your outstanding mortgage balance earlier, you may reduce the total interest charged over the life of the loan.

Even relatively small regular overpayments can potentially save thousands in interest and reduce your mortgage term by several years. This calculator helps estimate how additional monthly payments could affect your mortgage payoff timeline.

Reduce total mortgage interest costs

Pay off your mortgage earlier

Build home equity faster

Create more long-term flexibility

Things to consider before overpaying

Some lenders apply annual overpayment limits or early repayment charges. Before making large overpayments, check your mortgage terms carefully.

You may also want to consider whether paying down your mortgage is the best use of extra cash compared with building emergency savings, investing, or paying off higher-interest debt.

How this calculator helps

  • Your estimated interest savings
  • How much earlier you could become mortgage free
  • Your current monthly repayment estimate
  • The long-term effect of monthly overpayments

Tune your overpayment

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