What Are Mortgage Overpayments?
A mortgage overpayment is any amount you pay above your required monthly payment. If your monthly mortgage payment is £900 and you pay £1,100, the extra £200 is an overpayment. This additional money goes directly towards reducing your outstanding mortgage balance.
Because your balance reduces faster, you pay less interest over the life of the mortgage. Even small regular overpayments can make a significant difference. For example, overpaying by just £100 per month on a £200,000 mortgage at 5% over 25 years could save you over £17,000 in interest and knock more than three years off your mortgage term.
Types of Overpayment
There are two main ways to overpay:
- Regular overpayments: Increasing your monthly payment by a set amount. This is a disciplined approach that builds savings steadily over time.
- Lump sum overpayments: Making one-off additional payments when you have spare cash — perhaps from a bonus, inheritance, or savings.
Both achieve the same result: reducing your outstanding balance faster than your normal repayment schedule. Many borrowers use a combination of both, making regular small overpayments and adding lump sums when they can.
Overpayment Limits and Early Repayment Charges
Most UK mortgage deals allow you to overpay up to 10% of your outstanding balance each year without incurring an early repayment charge (ERC). Some lenders are more generous — offering 15% or 20% — while a few have no limit at all, particularly on variable rate or tracker mortgages.
If you overpay more than the allowed amount, you'll typically face an ERC on the excess. These charges can be significant — often 1% to 5% of the amount overpaid beyond the limit. Always check your mortgage terms before making large overpayments, and plan them within your annual allowance to avoid unnecessary charges.
How Overpayments Reduce Your Mortgage
When you overpay, the extra money reduces your outstanding capital balance. This means that less interest accrues each month, because interest is calculated on the remaining balance. Over time, this creates a compounding effect — not only are you paying off more capital, but less of each subsequent payment goes towards interest.
Most lenders apply overpayments in one of two ways: they either reduce your monthly payment (keeping the term the same) or keep your payment the same but shorten the term. Shortening the term is usually more financially beneficial because you become mortgage-free sooner and pay less total interest. Check with your lender which method they use, or whether you can choose.
Important: Your home may be repossessed if you do not keep up repayments on your mortgage. There will be a fee for mortgage advice. The actual rate available will depend on your circumstances. Think carefully before securing other debts against your home.