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    Overpayments Calculators

    Mortgage overpayment calculators

    Regular overpayments are the single most powerful way to cut lifetime mortgage cost. Model how much interest and time you'd save at your rate — before ERCs are triggered.

    Mortgage overpayment calculator

    Enter your figures, then add your name and phone to reveal the result. Free, no credit check.

    Get your result & a free broker sense-check

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    More overpayments calculators

    Lump sum overpayment calculator

    One-off overpayment (e.g. bonus, inheritance) — impact on term and interest.

    Monthly overpayment calculator

    Same-amount, every-month view — the most common setup.

    Mortgage payoff calculator

    Total months to clear the balance under a chosen overpayment strategy.

    Time saved calculator

    How many months/years the overpayment removes from the term.

    Interest saved calculator

    Cash interest saved over the remaining term.

    Every scenario above depends on lender-specific criteria (income multiples, ICR, stress rates, credit profile). A vetted FCA-regulated broker will run the exact numbers for your situation in one working day.

    Frequently asked questions

    Can I overpay a UK fixed-rate mortgage?

    Yes — most UK lenders allow 10% of the balance per calendar year during a fix without triggering an early repayment charge (ERC). Over that, ERC of 1–5% typically applies.

    Is it better to overpay my UK mortgage or invest?

    Rule of thumb: overpay if your mortgage rate is higher than your after-tax investment return. In a high-rate environment, overpaying is often the mathematically strongest risk-free option.

    Should I overpay my mortgage or my pension?

    Pension wins for higher-rate taxpayers because of 40% relief; overpaying wins if you're basic-rate and the mortgage rate is above ~4%. Do both if you can.

    Does overpaying reduce my UK mortgage term or payment?

    It reduces the term by default with most lenders (bigger interest saving). Ask to reduce the monthly payment instead if cashflow is tight — either is available on request.

    What's the early repayment charge on a UK mortgage?

    Usually 1–5% of the balance repaid over the allowance, tapering by year (5% year 1, 4% year 2, etc.). It's set out on page 3 of your mortgage offer.

    Can I overpay a Help to Buy Equity Loan?

    Yes — you can partially staircase from year 1 in blocks of 10% (min £2,500). Each staircase needs a fresh RICS valuation and repays a % of current property value, not original loan.

    Do UK lenders let me set up regular monthly overpayments?

    Yes — nearly all offer standing-order monthly overpayments online with no fee. Lump sums usually go via bank transfer with a reference number.