See what overpaying your mortgage actually saves
Enter your outstanding balance, remaining term and rate, then add a monthly or one-off overpayment to see how it changes your payoff date and the interest you pay. This is a calculation based on your own numbers, not a quote from any lender.
Understand what mortgage overpayments could do to your loan
The Mortgage Overpayment Calculator shows what happens to your outstanding balance and remaining term if you pay more than your monthly repayment. This guide is for homeowners who want to see the effect of overpaying on their own numbers before deciding whether it's worth doing. By the end you'll know how to read the result and what to check with your lender before acting on it.
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Enter your mortgage details
Add your outstanding balance, interest rate, and remaining term so the calculator has what it needs to work from.
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Add your overpayment amount
Enter the extra amount you're considering paying, either monthly or as a one-off lump sum, to see its effect.
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Read your result
Check how your remaining term and total interest change, and note that the real saving depends on your lender's terms for overpaying.
See what overpaying could do to your mortgage
Paying extra off your mortgage each month reduces what you owe faster, and that means less interest builds up over the rest of your term. Enter your outstanding balance and see roughly how much time and interest a regular overpayment could take off.
Your Mortgage Details
Your Savings Breakdown
New Mortgage Term
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Time Saved
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Current Monthly Payment
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This calculator gives an illustrative estimate based on the figures you enter, not a lender's actual terms. Check your mortgage offer document or ask your lender about any limits or charges on overpayments before making one.
See what overpaying could save you
Paying extra off your mortgage reduces the interest you're charged, because interest is calculated on what you still owe. This calculator uses your own outstanding balance, remaining term and repayment amount to show what a regular overpayment could do to your total interest and payoff date. It's a projection based on the numbers you enter, not a guarantee or a lender quote.
No sign-up needed · Works on any device · Estimates only
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