Remortgage Savings Calculator
A remortgage savings calculator shows whether moving your loan to a new deal would reduce what you pay each month. It compares your current payment with the payment on the new rate and term, then works out how long your closing costs take to pay back.
Enter the balance you still owe, your current and new interest rates, the years left on the loan, the new term and the closing costs. The calculator then shows your monthly saving, the time to break even and the total you save over the life of the loans after costs. Check the final figures with your lender or bank before you make a decision.
How to use the remortgage savings calculator
- Enter the balance left on your loan in pounds.
- Enter your current interest rate as a percentage.
- Enter the number of years left on your current loan.
- Enter the new interest rate offered as a percentage.
- Enter the new term in years.
- Enter the closing costs in pounds, then read the monthly saving, break-even time and total saved.
The formula
- Monthly payment = P × r ÷ (1 − (1 + r) ^ −n), where P is the amount borrowed, r the annual rate ÷ 12 ÷ 100 and n the number of months
- Monthly saving = payment now − new payment
- Break-even = closing costs ÷ monthly saving (months)
- Total saved = payment now × months left − (new payment × new months + closing costs)
Worked example
The figures below are made up to show the maths. They are not current prices, rates or product figures.
| Balance left on the loan | £250,000.00 |
|---|---|
| Current interest rate | 7% |
| Years left on the loan | 25 years |
| New interest rate | 6% |
| New term | 25 years |
| Closing costs | £4,000.00 |
- Monthly saving £156.19
- Closing costs paid back in 2 years 2 months
- Payment now £1,766.95
- New payment £1,610.75
- Total saved over the life of the loans (after closing costs) £42,858.35
Tips for an accurate answer
- Include all closing costs, such as arrangement and valuation fees, so the break-even time is accurate.
- Use the rate and term actually quoted to you, not an estimate, and confirm the figures with your lender.
- Compare the total saved as well as the monthly saving, because a longer new term can lower the payment while increasing the overall cost.
- Check whether your current deal has early repayment charges that could add to the cost of switching.
- Re-run the calculator with a few different new rates to see how sensitive the result is.
Questions people ask
Does remortgaging save you money?
It can, if the new rate and term lower your monthly payment or total cost after closing costs are included. Enter your current and new figures to see the monthly saving and the total saved in this calculator.
Can I use a remortgage savings calculator for a Nationwide deal?
Yes, as long as you enter the balance, rates, terms and closing costs from the Nationwide offer you have been given. The calculator works from the figures you enter, so check them with Nationwide before deciding.
How do I calculate what a remortgage will save me?
Enter your outstanding balance, current and new interest rates, years left, new term and closing costs. The calculator shows the monthly saving, how long the closing costs take to pay back and the total saved.
Can I compare a Barclays remortgage deal with this calculator?
Yes, by entering the Barclays rate, term and fees alongside your current loan details. Confirm the final figures with Barclays before making any decision.
What does the monthly saving show?
It is the difference between your payment now and your payment on the new deal. In the worked example, the payment falls from £1,766.95 to £1,610.75, a monthly saving of £156.19.
What are closing costs in this calculator?
Closing costs are the fees you pay to switch, which you enter as a single amount in pounds. The calculator divides them by the monthly saving to show how long it takes to pay them back.
What does the break-even time tell me?
It shows how many months of lower payments it takes to recover your closing costs. In the worked example, the costs of £4,000.00 are paid back in 2 years 2 months.
Why is the total saved different from the monthly saving multiplied by the months?
The total saved compares everything you pay on the current loan with everything you pay on the new loan, including the closing costs. This is why the worked example shows £42,858.35 rather than a simple multiple of the monthly saving.
Sources
This calculator uses the standard loan and interest formulas above and the numbers you type. It needs no outside figures.
An estimate from the numbers you enter, worked out with the formula shown. It is maths, not financial advice: your lender or bank has the final figures. Page checked 23 Oct 2026. Read the disclaimer