Answer four quick questions and see whether paying the early repayment charge to switch to a lower rate now beats waiting until your fix ends. Takes about a minute.
The outstanding balance you'd be remortgaging — it's on your latest mortgage statement.
All three are on your latest mortgage statement or annual mortgage review.
The penalty for leaving your current deal early, as a percentage of the balance. It's in your mortgage offer document — or pick a typical figure below.
ERCs usually step down each year of the fix — typically on the anniversary of completion. If yours drops soon, use the lower figure and consider timing the switch for just after the step-down.
The new rate available to you today — from a quote, a rate you've seen advertised, or our suggested typical figure.
Estimate only — not a guarantee or advice. Arrangement, legal and valuation fees aren't modelled, and lender criteria vary. Beyond the remaining fix, both options re-fix at whatever market rates apply. Your home may be repossessed if you do not keep up repayments on your mortgage.
We'll run the numbers against your real ERC schedule and answer any questions you have — before you pay anything.
Book Free ConsultationNo pressure. Just clear, expert advice.
This UK early remortgage calculator answers one question: is it worth paying the Early Repayment Charge to switch to a lower rate before your fixed deal ends, or is waiting cheaper? It compares your monthly payment on your current rate against the payment at the new rate, works out how many months the saving takes to recover the ERC, and shows the total amount you'd save — or lose — over the months remaining on your fix.
Most generic mortgage calculators only show the monthly payment side, which makes a lower rate look like an automatic win. The break-even test is what actually decides it: if the saving doesn't repay the ERC before your fix would have ended anyway, switching early costs you money. This calculator runs that test the same way a UK mortgage adviser would by hand.
For the situations where remortgaging early usually does add up — and the product-transfer option most homeowners overlook — see our guide to remortgaging during a fixed-term mortgage.
It compares two paths for the months remaining on your fixed deal:
You get your monthly payment on both rates, the total ERC cost in pounds, the break-even point in months, and the total saved or lost over the remaining fix period.
It's how many months the monthly saving takes to pay back the ERC. If you'd save £116 a month and the ERC is £5,000, you break even after roughly 43 months — so with only 30 months left on the fix, switching early would leave you worse off than waiting.
As a rough rule, the maths tends to favour switching with 24 or more months remaining and a rate gap of 1.5% or more. Below those thresholds, waiting — or a product transfer with your existing lender — is usually the better answer.
Usually, yes. Most lenders structure the ERC as a stepped percentage that falls each year of the fix — for example 5% in year one of a five-year fix, down to 1% in the final year. The step-down typically happens on the anniversary of completion, not the calendar year.
That makes timing one of the simplest wins available: if your ERC steps down next month, completing the switch just after the step-down can save thousands. Some products charge a flat percentage for the whole fix instead — your exact schedule is in your mortgage offer document.
Often — especially in the final months of a fix. Most lenders let you secure a new deal three to six months before your current fix ends, timed to start the day after the ERC expires: no charge, no legal process, and usually no new affordability check.
The trade-off is that a product transfer limits you to your existing lender's range, which may not be the best rate available. We compare both routes against deals from 90+ lenders before recommending either — the full breakdown is in our guide to remortgaging during a fixed term.
