Tiny Toolkit

Mortgage Overpayment Calculator

See exactly how much interest you save — and how many years you cut off — by adding even a small extra payment each month. Enter your remaining balance, rate, and term, then adjust the extra payment amount to find the right balance between savings and cash flow. Results update instantly.

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Frequently Asked Questions

How does making extra payments save money?
Extra payments reduce your outstanding balance faster, which means less balance accrues interest each month. This compounds over time — even a small extra payment each month can save years off the loan.
Can I make a one-time extra payment instead of monthly?
This calculator models a consistent extra monthly payment. For a one-time lump sum, reduce your remaining balance by that amount and re-run the standard calculation to see the effect.
Does my lender automatically apply extra payments to the principal?
Not always. Check with your lender that overpayments are applied to the principal balance, not to future scheduled payments, to maximise the interest savings.

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