Mortgage Overpayment Calculator UK – Interest Saved & Term Reduced

Most people know that overpaying their mortgage saves money — but the numbers are rarely visible until you actually run them. This calculator shows you exactly what happens when you make extra payments: how much interest you save, how many years you cut from your term, and how the impact shifts depending on whether you pay monthly or in lump sums.

It is designed for UK homeowners at any stage of their mortgage — whether you have just started or are a few years in, and whether you are overpaying £50 a month or planning a larger one-off payment. You can compare strategies side by side so the decision is clear, not theoretical.

The tool also helps you think through the trade-offs. Overpaying is not always the right priority — if you carry high-interest debt, that may come first. This calculator gives you the numbers to make that call with confidence. Always check your lender's overpayment limit and any early repayment charges before committing.