Home Mortgages Mortgage calculators & tools Interest rate change calculator

Interest rate change calculator

If you have a Standard Variable Rate or Tracker Rate Mortgage, your interest rate – and so your monthly payments – could go up as well as down. Enter your details below to see how rate changes will affect what you pay.

This tool is only for Repayment Mortgages.

This is a guide of what could happen. It only looks at your minimum monthly payment and doesn’t include any voluntary overpayments you might make.

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
£0
Estimated monthly payment
£0

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

Contact us today

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

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


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

03 456 100 198

Mon to Fri 8am - 9pm and Sat 8am - 5.30pm