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Mortgage overpayment calculator

Thinking of making an overpayment? Know with your first direct mortgage you can make unlimited overpayments towards your borrowing - but you might have an Early Repayment Charge if you repay your whole mortgage during the fixed rate period.

Making overpayments on your mortgage should mean you pay it off quicker and pay less interest overall – enter your details into this calculator to get an idea of how much faster and how much you could save.

Your mortgage details

You can find these details on your most recent statement. If you have more than one Repayment Mortgage account, you’ll need to do separate calculations for each.

Your mortgage details

What you could save by overpaying

What could you save by overpaying

A monthly overpayment of
could save you
and reduce your term by
months over the term of your mortgage.

The benefits of overpaying

With overpayments

Monthly payment
Total interest payable

Without overpaying

Monthly payment
Total interest payable

How we calculate these savings

  • the calculator assumes your interest rate will stay the same for the term of your mortgage
  • we’ve evened out the months so they’re all the same length – 30.4 days each – so monthly interest will be consistent
  • repayments are rounded up or down to the nearest pound
  • we’ve rounded time saved down to the closest month
  • interest is calculated daily and added monthly
  • interest saved is rounded up or down to the nearest pound
  • the calculator assumes that the overpayments illustrated remain constant throughout the term of the mortgage and are made on a monthly basis – if overpayments are made on an adhoc basis, this will reduce the amount of interest paid but not the loan term
  • the calculator doesn’t factor in any charges for early repayments.

Please note – the information here is for illustrative purposes only and isn’t a precise calculation. The tool doesn’t include all of the details you need to either make an overpayment or choose a mortgage. Make sure you read the separate Mortgage Illustration before you choose a mortgage.

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