Early Repayment Charges (ERCs): A Complete Guide
What they are, how to calculate them, and when overpaying is still worth it.
Before committing to mortgage overpayments, you need to understand Early Repayment Charges (ERCs) — the fees your lender can charge if you repay more than allowed during a fixed-rate or discounted deal period. This guide explains exactly how ERCs work, how to calculate them, and how to decide whether overpaying is still financially worthwhile.
What Is an Early Repayment Charge?
An Early Repayment Charge is a fee imposed by a mortgage lender when you repay your mortgage — or a significant portion of it — before the agreed fixed or discount deal period ends. Lenders include ERCs because they borrow money at wholesale rates to fund your mortgage, and they price that borrowing assuming you will pay interest for the full agreed term. Repaying early disrupts that arrangement.
ERCs typically apply during the fixed, tracker, or discount deal period — often 2, 3, or 5 years. Once you move to your lender's Standard Variable Rate (SVR), ERCs usually no longer apply. This is why many borrowers choose to overpay significantly after their deal ends, or to remortgage to a product with a higher ERC-free overpayment allowance.
How ERCs Are Calculated
UK ERCs are almost always expressed as a percentage of the outstanding mortgage balance at the point of overpayment, and they are typically tiered — reducing each year of the deal period:
| Year of Deal | Typical ERC Rate | On £250k Balance | On £200k Balance |
|---|---|---|---|
| Year 1 | 5% | £12,500 | £10,000 |
| Year 2 | 4% | £10,000 | £8,000 |
| Year 3 | 3% | £7,500 | £6,000 |
| Year 4 | 2% | £5,000 | £4,000 |
| Year 5 | 1% | £2,500 | £2,000 |
Illustrative only. Actual ERC rates vary significantly by lender and product. Always check your mortgage offer document.
The 10% Annual Overpayment Allowance
Most UK fixed-rate mortgage products allow you to overpay up to 10% of the outstanding balance per year without triggering an ERC. This is a standardised industry threshold, though the exact figure varies — some lenders allow 5%, others 20%, and some products allow unlimited overpayment.
Example: 10% Allowance in Practice
On a £250,000 outstanding balance, your ERC-free overpayment allowance for the year is £25,000. Spread monthly, that is approximately £2,083 per month above your standard payment. For most borrowers targeting £100–500/month in overpayments, the 10% threshold is rarely a constraint.
The allowance is typically measured on a calendar year basis (or mortgage year, depending on the lender). Unused allowance does not usually roll over — it resets each year.
How to Find Your ERC Details
Read your original Mortgage Offer document
Your lender must disclose all ERC rates in the mortgage offer. Look for the section titled 'Early Repayment Charges' — it will list the percentage and the period it applies.
Check your lender's online portal
Most UK lenders (Halifax, Nationwide, Barclays, NatWest, etc.) show your current ERC, allowance remaining, and deal end date in the mortgage section of your account.
Call your lender's mortgage team
Ask: 'What is my current annual overpayment allowance? What ERC applies if I exceed it, and when does it expire?' They are required to provide this information.
Use the Key Facts Illustration (KFI)
If you are remortgaging or switching deals, the KFI or European Standardised Information Sheet (ESIS) provided by brokers clearly shows all charges.
Is Overpaying Still Worth It When ERCs Apply?
Even when an ERC applies, overpaying can sometimes be the right decision — particularly if a large lump sum becomes available (bonus, inheritance, property sale proceeds). The test is simple: does the interest saved over the remaining term exceed the ERC cost?
Worked Example
Scenario
- • Outstanding balance: £200,000
- • Rate: 5.5% fixed
- • 3 years remaining on deal
- • ERC: 2% of balance = £4,000
- • Proposed lump sum: £20,000
Interest saved by overpaying now
- • Interest on £20,000 at 5.5% over 3 yrs ≈ £3,300
- • ERC cost: £20,000 × 2% = £400
- • Net saving: ≈ £2,900
- • Verdict: Overpay (saving exceeds penalty)
Simplified illustrative example. Use the REPAYLY mortgage calculator for precise projections based on your own figures.
Should You Wait Until Your Deal Ends?
If your ERC period ends within the next few months, it is often sensible to wait before making a large lump-sum overpayment — particularly if the ERC would consume most of the interest saving. For regular monthly overpayments within the allowance, however, there is rarely a reason to delay.
Common Mistake to Avoid
Many borrowers mistakenly believe they must wait for their deal to end before making any overpayment. This is incorrect. Regular monthly overpayments within the annual allowance (typically 10% of balance) are ERC-free. Only lump sums or overpayments above the allowance trigger charges.
Model the Savings vs the ERC Cost
Use the REPAYLY mortgage calculator to enter your exact figures and see whether the interest saving from overpaying exceeds any applicable Early Repayment Charge.
Financial Disclaimer
This guide is for educational purposes only and does not constitute financial or regulated mortgage advice. Early Repayment Charge rates, allowances, and deal structures vary significantly between lenders and mortgage products. Always read your mortgage offer documentation carefully and consult a qualified Independent Financial Adviser (IFA) or mortgage broker regulated by the Financial Conduct Authority (FCA) before making decisions that could incur charges.