See How Much You Could Save on Your UK Mortgage.
Free calculator showing how overpayments could cut years off your mortgage and reduce the interest you pay.
Free UK mortgage calculator. No email required.
Free. No sign-up. Takes under a minute
Illustration: a £152,000 mortgage at 4.5% with 20 years 10 months left, with £0, £100, £200, £300 and £450 a month extra. Each dot on the line is a mortgage-free date. These are estimates: they assume the rate stays the same for the whole term and ignore fees and early repayment charges.
Step 1
Enter Your Mortgage Details
Add your current mortgage balance, interest rate, remaining term and any planned overpayments. No personal details or sign-up required. Start in the mortgage overpayment calculator.
Step 2
Instantly See Your Potential Savings
We calculate how overpayments could reduce the interest you pay and shorten your mortgage term, using clear UK-focused assumptions.
Step 3
Explore Your Options
Adjust overpayment amounts to compare scenarios and understand how they might affect your situation before speaking to a lender or adviser.
Free to use. UK-focused. Results are estimates only
Mortgage Overpayment Calculator (UK)
This mortgage overpayment calculator helps UK homeowners understand how making monthly or one-off overpayments can reduce both the total interest paid and the length of their mortgage. By entering your balance, interest rate, and overpayment amount, you can see how even small changes may affect your interest and term over time.
Overpayments reduce your outstanding balance earlier, which usually means less interest is charged overall. This can shorten your mortgage term, lower future monthly payments or, in some cases, both, depending on how your lender applies overpayments.
The calculator is designed for UK mortgages and does not account for your lender’s terms, fees or early repayment charges. Results are estimates only and should be used for planning rather than financial advice. Check your lender’s terms before overpaying, as early repayment charges may apply.
Mortgage Overpayment FAQs (UK)
Can you use the calculator for free without signing up?
Yes. The mortgage overpayment calculator is free to use, with no sign-up, no email address and no personal details needed, and no credit checks. Enter your current balance, interest rate, remaining term and a monthly overpayment, and the results update as you type, showing the interest you could save and how much sooner you could be mortgage-free. Results are estimates only and not financial advice. Try the calculator.
Who is this calculator best for?
It's built for UK homeowners with a capital-and-interest repayment mortgage who want to see how regular monthly overpayments could cut their interest and mortgage term. It doesn't model interest-only mortgages. Use the figures from your latest mortgage statement: your current balance and remaining term, not the original loan. It assumes one interest rate for the rest of the term, so if you're mid-fix, re-run it with your new rate when you remortgage. See how to use a mortgage savings calculator.
Mortgage Guides & Insights
Straightforward UK mortgage guides to help you understand overpayments, interest, and long term savings.
What Is an Early Repayment Charge on a UK Mortgage?
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Can You Overpay a Tracker or Variable Rate Mortgage in the UK?
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When Does Your Mortgage Overpayment Allowance Reset?
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Is It Worth Paying an Early Repayment Charge to Overpay More?
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Overpaying Your Mortgage by £200 a Month: What Could It Do?
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Overpaying Your Mortgage by £300 a Month: What Could It Do?
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Overpaying Your Mortgage by £500 a Month: What Could It Do?
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Overpaying Your Mortgage by £1,000 a Month: What Could It Do?
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How Does Your Mortgage Rate Change What Overpaying Does?
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How Much Would You Need to Overpay to Clear Your Mortgage Sooner?
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