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Interest rate change calculator

What If your mortgage rate changes?

Our Interest rate calculator could be helpful if you’re coming to the end of a fixed-rate period, shopping for a new deal or you’re thinking about potential changes to the Bank of England base rate.

See how a change of interest rates could affect your monthly mortgage payments.

This tool is only for Repayment Mortgages.

Your 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 monthly repayments

Your monthly repayments

Remaining term

Your monthly repayments

The monthly payment is the minimum you would need to pay.

Current monthly payment
Estimated monthly payment

How we worked this out

  • the calculator assumes your new interest rate will stay the same for the rest of your mortgage term
  • 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
  • interest is calculated daily and added monthly
  • we’ve not accounted for any overpayments.

Find the mortgage for you

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If you want to: Find out more information about your existing mortgage rate

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If you want to: Move house, remortgage, discuss rates or borrow more

New to first direct

0800 48 24 48

Mon to Sat 8am - 8pm and Sun 9am - 8pm

Existing first direct customers:

03 456 100 103

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If you have: Completion questions, payment changes, statement requests, or to pay off your mortgage

03 456 100 198

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If you have: An ongoing mortgage application

03 456 100 173

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