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Interest rate calculator

Call us free on
0800 316 4071

Should I stay or should I go?

Your mortgage is likely to be the biggest financial commitment you have. Therefore it makes sense to regularly review your current one to check it’s still the best for you.

Mortgages commonly have early repayment charges, which can make leaving them quite costly. A new mortgage will often need a much lower interest rate to make leaving and paying these charges worthwhile.

The calculator below will help indicate what interest rate a new mortgage would need to save you money.

You can then refer to our mortgage rate table to see if there are mortgage rates low enough.

Please make sure the figures you enter are as accurate as possible. This will ensure the result provided is as realistic as possible.



Base Rate Calculator


Penalty fees you have to pay if you want to leave your mortgage during a specified period. This is most likely to be within the fixed rate deal you are currently on.


Months left on your fixed term deal.


Remaining sum on your mortgage required.


The current amount of your mortgage where the monthly payment goes toward paying back the money borrowed and the interest charged for borrowing.


The current amount of your mortgage where the monthly payment only goes toward paying the interest for borrowing the money – not repaying the capital borrowed.

years months

Length of time until your current mortgage will be paid off.



Current interest rate you are paying on your mortgage.


Any interest rate higher than this wouldn’t save the repayment charge over the fixed term.



IMPORTANT – Remember this is a rough calculation only and does not include any costs such as lenders fees, solicitors’ costs or stamp duty. This information does not contain all of the details you need to choose a mortgage and cannot be relied upon in relation to any remortgage application. You should speak to an independent mortgage adviser to get an accurate quote before taking any action.

Does it look like the mortgage rates might be low enough to make switching worthwhile? Would you like to speak to one of our mortgage advisers to receive impartial personalised advice on whether switching is the right thing for you? If so, please call us for free from a mobile or landline on 0117 981 7787

Useful Guides

Our full remortgaging guide has the information you need to help you understand your mortgage options and to get the best deal. We also have tips on how to save on your mortgage.

We’re here to help you

Contact Which? Mortgage Advisers free from a mobile or landline on 0800 316 4071

Or we’ll arrange to call you

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Your home may be repossessed if you do not keep up repayments on your mortgage.

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