Mortgage Interest Rate Calculator

How to use this tool

1. Enter the remaining mortgage term in years and months.
2. Enter the current mortgage balance and current interest rate.
3. Enter the interest rate change to compare and press Calculate.

Best for

• Checking the possible impact of a rate rise or cut
• Planning near the end of a fixed-rate mortgage period
• Comparing monthly repayment estimates before shopping for a new deal
• Understanding how the Bank of England base-rate direction might affect a repayment mortgage

Tips

• This calculator is for repayment mortgages, not interest-only mortgages.
• The result is an estimate and does not include fees, insurance, overpayments or product-specific rules.
• Use your latest mortgage statement for the balance and remaining term.
• Enter a negative change for a rate decrease, such as -1.25.

Good to know

Mortgage payment estimates use the standard repayment formula with monthly compounding. Real lender quotes can differ because of fees, daily interest methods, rounding and account-specific rules.

This is not financial advice. Use it as a quick planning estimate, then check important figures with your lender or a qualified adviser.

Frequently asked questions