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ClearMoney Calcs

Remortgage Calculator (UK)

Enter your balance, current rate and years left, then the new rate, term, deal length and fees to see your payment now and after remortgaging, what you'd save over the deal and the month the savings cover the costs.

  • Updated
  • Formula tested
  • Private: runs in your browser

Your remortgage

What you still owe

Current mortgage
New deal

Arrangement, valuation, legal

Of the balance, if any

Monthly saving

£203.26

£1,342.03 now → £1,138.77 a month after remortgaging

Saving over 5 years

£16,397

Interest saved minus all costs

Break-even

Month 4

When savings cover the costs

Switching costs

£999

Fees only

Interest over 5 years

£37,186

vs £54,582 at 6.5%

Assumes fees are paid upfront and both rates stay fixed for the deal. Compares interest, so a longer new term isn’t counted as a saving.

Results are estimates for educational purposes and are not financial advice.

How to use this remortgage calculator

  1. Mortgage balance: what you still owe, from your latest statement or online account.
  2. Current mortgage: your current rate and how many years are left on the mortgage.
  3. New deal: the rate you've been offered, the term you'd take and whether it's a 2-year or 5-year deal.
  4. Fees: arrangement, valuation and legal fees for the new deal, added together.
  5. Early repayment charge: if leaving your current deal early carries a charge, enter it as a percentage of the balance. Leave it at 0 if your deal has ended or has no charge.

You'll see your payment now and after remortgaging, the monthly difference, the overall saving over the deal after all costs, and the break-even month.

How the comparison works

Comparing interest rather than payments matters when the term changes. Stretching the same balance over more years lowers the payment, but because you repay the loan more slowly, you pay more interest. The calculator counts that honestly instead of treating a lower payment as a saving.

Worked example

Now suppose the current deal still has an early repayment charge of 2%, and the new deal is a 2-year fix. The charge is 2% × £180,000 = £3,600, so switching costs £4,599 in total. The interest saved over the two years still outweighs that, leaving a saving of £2,523.31, but break-even moves out to month 16. If you expected to move home within that time, waiting for the charge to end might be the better choice.

When remortgaging makes sense

  • Your fixed rate is ending. When a deal ends, most mortgages move onto the lender's standard variable rate. Comparing that rate with new deals is the most common reason to remortgage.
  • Rates have fallen. If new deals are much cheaper than your current rate, the saving can outweigh even an early repayment charge, as the example shows.
  • You want to change the term. You can shorten the term to become mortgage-free sooner, or lengthen it to lower payments. The calculator shows the effect on interest either way.
  • Your loan-to-value has improved. If you've paid down the mortgage or your home has gone up in value, you may qualify for a lower loan-to-value band and a better rate.

Remortgaging vs a product transfer

A product transfer is a new deal with your current lender. It often has lower fees and can be quicker, because there's usually less paperwork. A remortgage moves your mortgage to a new lender, which may offer a better rate but can involve valuation and legal work. Run both offers through the calculator with their own rates and fees: the overall saving makes them easy to compare.

Costs to include

Add every cost of switching to the fees box so the comparison is fair:

  • arrangement or product fees
  • valuation fees, if charged
  • legal or conveyancing fees, if charged
  • any broker fee

Many deals advertise "free" valuations or legal work, and some offer cashback. If a deal includes cashback, subtract it from the fees you enter.

Overpaying instead of switching

If switching doesn't save much, overpaying your current mortgage can be another way to cut interest. Our mortgage overpayment calculator shows how much a monthly overpayment or lump sum would save. To check payments for a new purchase, use the UK mortgage calculator, or the first-time buyer mortgage calculator if you're buying your first home.

What this calculator doesn't include

The results assume both rates stay fixed for the comparison and that fees are paid upfront. They don't include changes to your rate after the new deal ends, cashback, or the effect of adding fees to the loan. Check your current lender's redemption statement for the exact balance and any early repayment charge, and confirm the new deal's terms with the lender or a mortgage adviser before switching.

Checklist before you switch

  • Find your deal end date and whether an early repayment charge applies until then.
  • Get a redemption figure from your current lender so the balance you enter is exact.
  • Compare like with like: use the same term for both options first, then try a different term to see its effect on interest.
  • Add up every fee, including any you'd add to the loan.
  • Think about your plans. If you might move or sell before the break-even month, a deal with lower fees, or one you can take with you to a new home, may suit you better.

Frequently asked questions

Is it worth remortgaging?

It's usually worth it when the interest you'd save over the new deal is more than the cost of switching: arrangement and other fees plus any early repayment charge on your current deal. The calculator shows that overall saving and the month when the savings first cover the costs.

What is an early repayment charge?

An early repayment charge (ERC) is a fee some lenders charge if you repay or leave a mortgage deal before it ends, usually set as a percentage of the balance. Your mortgage offer or annual statement says whether one applies and how much it is.

What is the break-even month?

It's the first month in which the interest you've saved by switching adds up to more than the fees and any early repayment charge. If you'd sell or move again before then, the switch may cost you money overall.

Why does the calculator compare interest rather than payments?

Because a longer term lowers the monthly payment without making the mortgage cheaper: you'd simply repay the loan more slowly and pay more interest. Comparing the interest paid during the deal shows the real saving, while the payment figures show the effect on your monthly budget.

Should I add the fees to the mortgage?

Some lenders let you add the arrangement fee to the loan. That avoids paying it upfront, but you'll pay interest on it for the rest of the term. This calculator assumes fees are paid upfront; adding them to the loan makes the switch slightly more expensive.

When should I start looking at a new deal?

Many lenders let you secure a new deal some months before your current one ends, so you can move straight onto it instead of the lender's standard variable rate. Check your lender's rules and your deal's end date.

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