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  3. Overpayment calculator

Ultimate Mortgage Calculator

8 calculators to compare mortgages, from ditching your fix to saving for a deposit

Overpayment calculator

Before overpaying your mortgage, check that your lender allows you to overpay it penalty-free, and if there are any limits as to how much you can overpay.

If you're on your lender's standard variable rate or you're on a tracker mortgage, there is normally no limit on how much you can overpay your mortgage by. However, fixed-rate mortgages typically have an annual overpayment limit of 10% of your TOTAL outstanding mortgage balance.

As the exact method of how this 10% is calculated varies by lender, use our calculator as a rough guide, and be sure to speak to your lender to work out exactly how much you can overpay by.

Also ensure that any overpayment you make goes to reduce the debt (so shortening the term) rather than reducing your monthly payments. This calculator assumes you reduce the mortgage debt, which is the main benefit of overpaying.

1 to 40 years

Mortgage type

Note. Typically you're only allowed to overpay by 10% of your outstanding mortgage balance per year, so bear this in mind in particular if you wish to make recurring overpayments more than once a year.

One-off overpayment

See how much you'd earn putting the same amount into a savings account (repayment mortgages only).

Do you pay tax on savings interest?
If you're not sure, most people don't pay tax unless they've a lot of savings, so leave it as 'None'

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IMPORTANT! Please read...

This information is computer generated. The results are rounded and rely on certain assumptions. This calculator is a ready reckoner that's been designed to give a useful general indication of costs.

It's important you always get a specific quote from the lender and double-check the price yourself before acting on the information. We cannot accept responsibility for any errors.

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