Stamp Duty CalculatorEarly Repayment Charge Calculator
Work out the ERC on a UK fixed-rate mortgage break — paying off, remortgaging early, or overpaying above your annual allowance. Also computes whether a remortgage still saves money net of the charge.
Your mortgage
Is it worth paying the ERC?
How UK early repayment charges work
Fixed-rate mortgages are priced on the assumption you'll stay for the whole fix period (2, 3, 5, 7 or 10 years). If you repay above the ERC-free allowance (usually 10% of balance per calendar year) or exit the deal entirely before the fix ends, the lender charges a percentage of the overpaid amount. ERCs typically step down over the fix: 5% in year 1 → 4% in year 2 → 3% in year 3 → 2% in year 4 → 1% in year 5.
When paying an ERC still saves money
If the new rate is materially lower and you have 2+ years of fix left, the interest saving usually exceeds the one-off ERC. On a £200,000 balance, a 1.25pp rate drop saves roughly £2,500/year — a 3% ERC (£6,000) breaks even in just under 2.5 years. Factor in the remortgage fees too.
Frequently asked questions
What ERC rate will I pay?
Check your original mortgage offer under "Early Repayment Charges". It will list the tiered % by year. Typical UK fixed-rate ERCs are 1-5% stepping down.
Does the 10% allowance reset each year?
Yes, on most products — on either the calendar year or your anniversary, lender-dependent. Unused allowance usually doesn't carry over.
Is porting better than paying the ERC?
Often yes if you're moving home — porting takes the mortgage with you and avoids the ERC. Not all products are portable; new borrowing above the ported amount uses the lender's current rates.
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Last reviewed: 1 October 2026.