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Mortgage Rate Change Calculator

See how your monthly mortgage payments could change when your current fixed deal ends. Enter your current mortgage details, the time left on your deal, and an estimated new rate to compare where you are now with what could come next.

Calculator inputs

Estimated current LTV 74.00%
Mortgage term remaining 23 years 6 months
Current deal remaining 2 years 4 months

Projected payment summary

Current estimated monthly payment £839.84
Monthly change +£322.80
Balance when deal ends £170,585.98
Current mortgage type Repayment
Time left on current deal 2 years 4 months
Total mortgage term remaining now 23 years 6 months
Remaining term after deal ends 21 years 2 months
Estimated payment change (%) +38.44%
Estimated interest paid during current deal £9,101.51
Projected interest after current deal £124,726.11
Total projected remaining interest £133,827.62

Before vs after deal end

Stage Rate Payment Balance Term left
Now 2.19% £839.84 £185,000.00 23 years 6 months
When current deal ends 5.75% £1,162.64 £170,585.98 21 years 2 months

Payment sensitivity to future rates

Future rate Estimated payment Change vs current
4.75% £1,066.08 +£226.24
5.25% £1,113.81 +£273.97
5.75% £1,162.64 +£322.80
6.25% £1,212.55 +£372.71
6.75% £1,263.51 +£423.67

How this mortgage rate change calculator works

This calculator estimates your current monthly mortgage payment using your remaining balance, current interest rate and remaining term. It then projects the balance likely to remain when your current fixed deal ends. Using your estimated next rate and the shorter remaining term, it calculates a new monthly payment so you can compare the difference.

What to enter

Enter your current mortgage balance, optional property value, your current interest rate, how long is left on the mortgage, and how long remains on your current fixed deal. Then enter an estimated rate for the next deal or follow-on rate.

Repayment vs interest-only

For repayment mortgages, the calculator assumes you keep paying down capital during the current deal, so the balance at the end of the deal should be lower. For interest-only mortgages, the balance is assumed to stay the same because the monthly payment usually covers interest only.

Important note

This is a planning estimate only. Actual lender products, product fees, standard variable rates, overpayments, payment dates and rate changes can all affect the real figures.

This calculator provides general estimates only and does not constitute financial, tax, or legal advice.