Calculate how much you could save on interest and reduce your mortgage term by making extra payments. Enter your mortgage details below to see the potential savings from overpayments.
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Discover proven strategies, UK-specific rules, and expert tips to pay off your mortgage early and save thousands in interest.
Read Our Complete Guide →Mortgage overpayments are extra payments you make on top of your regular monthly mortgage payment. These extra payments go directly towards reducing your principal balance, which reduces the interest you'll pay over the life of the loan and can significantly shorten your mortgage term.
The amount you can save depends on your mortgage balance, interest rate, and the size of your overpayments. Even small regular overpayments can save thousands of pounds in interest and reduce your mortgage term by several years.
Many UK mortgages allow you to overpay up to 10% of the outstanding balance per year without penalty. Check your mortgage agreement for specific terms, as some lenders may charge early repayment fees for overpayments exceeding this limit.
This depends on your personal circumstances. If your mortgage interest rate is higher than what you'd earn in savings, overpaying typically makes financial sense. However, ensure you have an emergency fund first and consider other debts with higher interest rates.
When you overpay, you typically have two options: reduce the term (pay off earlier with same monthly payment) or reduce the monthly payment (keep same term but pay less each month). This calculator shows the benefit of reducing the term, which typically saves more interest overall.
This calculator provides accurate estimates based on standard mortgage formulas. However, actual savings may vary depending on your specific mortgage terms, when overpayments are made, and your lender's policies. Always consult with your mortgage provider for precise figures.
When you make a mortgage overpayment, the extra money goes directly towards reducing your outstanding mortgage balance (the principal). Because interest is calculated on the remaining balance, a smaller balance means you pay less interest each month going forward. This creates a compounding effect: you owe less, so less interest accrues, which means more of your regular payment goes towards the principal, reducing your balance even faster.
For example, if you have a £200,000 mortgage at 5% interest over 25 years, your monthly repayment would be approximately £1,169. If you overpay by just £100 per month from the start, you could save over £23,000 in interest and pay off your mortgage nearly 4 years early. The earlier you start overpaying, the greater the benefit, because you reduce the balance on which interest compounds for a longer period.
The type of mortgage you have significantly affects how overpayments work and whether you will face charges for making them:
Fixed-rate mortgages lock your interest rate for a set period (typically 2 or 5 years). Most fixed-rate deals allow you to overpay up to 10% of the outstanding balance per year without penalty. Any overpayment above this limit will usually trigger an Early Repayment Charge (ERC). Once the fixed period ends and you move to the lender's Standard Variable Rate (SVR), you can typically overpay unlimited amounts.
Variable-rate mortgages (also called tracker or SVR mortgages) often have more generous overpayment terms. Many tracker mortgages allow unlimited overpayments without penalty. However, always check your specific mortgage deed, as some tracker deals during an introductory period may still have restrictions.
Offset mortgages link your savings account to your mortgage. Your savings balance is offset against the mortgage balance, so you only pay interest on the difference. This effectively acts like a flexible overpayment because you can access your savings if needed, unlike traditional overpayments which are usually locked away.
ERCs are fees your lender charges if you repay your mortgage early or overpay beyond the allowed limit during a special rate period. These charges exist because the lender expected to earn interest over the agreed term. ERCs are typically calculated as a percentage of the amount overpaid beyond the limit, and can range from 1% to 5% depending on how far into the deal you are.
For example, if your ERC is 3% and you overpay £10,000 beyond the annual limit, you would be charged £300. ERCs usually decrease each year of the deal. A typical 5-year fixed mortgage might have ERCs of 5% in year one, 4% in year two, 3% in year three, and so on. It is crucial to check your mortgage offer document for the exact ERC schedule before making large overpayments.
Some lenders calculate the 10% overpayment allowance from the start of the calendar year, while others use the anniversary of the mortgage. If you are planning a large overpayment, contact your lender to confirm when your overpayment year resets.
The savings from overpayments depend on three main factors: your interest rate, your remaining balance, and how much and how often you overpay. Here are some realistic examples based on a 25-year repayment mortgage:
Even a one-off lump sum overpayment can make a significant difference. A single £5,000 overpayment on a £200,000 mortgage at 5% could save you over £8,000 in interest over the remaining term. Use the calculator above to model your exact situation.
Both lump sum and regular overpayments reduce your mortgage, but they work slightly differently. Regular overpayments (e.g., an extra £100 per month) build a habit and steadily chip away at your balance. They are easier to budget for and keep you within the typical 10% annual overpayment allowance. Lump sum overpayments (e.g., using a bonus, inheritance, or savings) give an immediate boost to your balance reduction.
From a pure interest-saving perspective, making the overpayment as early as possible saves the most money, because you reduce the balance on which interest is charged for the longest time. If you receive a lump sum, overpaying sooner rather than later is generally better, provided you stay within your ERC-free allowance. Many homeowners combine both strategies: regular monthly overpayments plus occasional lump sums from bonuses or tax refunds.
While overpaying can be beneficial, it is not always the best use of your money. Consider these situations where you might be better off doing something else:
The right choice depends on your individual circumstances, risk tolerance, and financial goals. Many people take a balanced approach, splitting spare money between overpayments, savings, and investments.
In most cases, no. Once you have made an overpayment on a standard repayment mortgage, the money is gone and cannot be withdrawn. Some lenders offer a "borrow back" facility, but this is not common. Offset mortgages are the exception: because your savings sit in a linked account, you can withdraw them at any time. If flexibility is important to you, consider an offset mortgage or keep funds in an accessible savings account instead of overpaying.
This depends on your lender. Some lenders automatically reduce your monthly payment when you overpay, keeping the term the same. Others reduce the term while keeping your payment the same, which saves more interest overall. Some lenders let you choose. Reducing the term is generally more beneficial because you pay off the mortgage sooner and pay less total interest. Contact your lender to find out their policy and whether you can specify your preference.
The process varies by lender. Many now allow overpayments through online banking or their mobile app. Others require you to set up a standing order to a specific overpayment account, or you may need to call them to make a one-off payment. Check your lender's website or call them to find out the exact process. Make sure you specify that the payment is an overpayment and not an advance payment for future months.
Yes, it can be very worthwhile. Overpaying before remortgaging reduces your loan-to-value (LTV) ratio, which could move you into a lower LTV bracket and qualify you for better interest rates. For example, dropping from 82% LTV to 75% LTV by overpaying could unlock significantly better mortgage rates, saving you thousands over your next deal. Even small overpayments can push you over a threshold if you are close to a boundary.
The interest you save by overpaying your mortgage is not taxable, making it an effective guaranteed return. If your mortgage rate is 5%, every pound you overpay effectively earns you a 5% tax-free return. Compare this to savings interest, which is taxable above the Personal Savings Allowance (£1,000 for basic-rate taxpayers, £500 for higher-rate taxpayers). For higher-rate taxpayers, a 5% mortgage overpayment return is equivalent to earning roughly 8.3% gross in a taxable savings account.