Early repayment charge (ERC)

A fee some fixed-rate mortgages apply when overpayments exceed the lender's allowed threshold during the fixed period — commonly up to 10% of the outstanding balance per year in the UK. The charge is typically 1–5% of the amount over the allowance and is set by the lender's own terms, not by law. Overpaying past the threshold can erase some or all of the interest saved, so the annual allowance should be checked before making a large lump-sum payment.