Your mortgage details
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%
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Total interest saved
£0
over the life of your mortgage
0Years saved
0Months saved
0New term
£0Overpayment/month
For guidance only — not financial, tax or legal advice. Verify with a qualified professional.
About mortgage overpayments
Is it always worth overpaying my mortgage?
Usually yes, if your mortgage rate is higher than the interest you'd earn saving. With mortgage rates at 4–6% in 2026 and easy-access savings at 4–5%, overpaying often wins — especially once you account for tax on savings interest. Always check for early repayment charges (ERCs) first.
How much can I overpay without a penalty?
Most fixed-rate mortgages allow overpayments of up to 10% of the outstanding balance per year without triggering an early repayment charge. Check your mortgage offer document or call your lender to confirm your specific limit.
Does overpaying reduce my monthly payment or my term?
It depends on your lender. Most by default reduce the term (so you pay it off sooner) rather than reducing your monthly payment. You can usually choose — ask your lender. Reducing the term saves more interest overall.
What about offset mortgages?
With an offset mortgage, your savings sit in a linked account and reduce the balance you're charged interest on — without actually paying it down. This calculator is for standard repayment mortgages. Offset calculations work differently as the savings remain accessible.
Should I overpay or build an emergency fund?
Build the emergency fund first — 3 to 6 months of expenses in easy-access savings. Once that's in place, overpaying your mortgage is one of the best guaranteed returns available. Money paid into your mortgage is locked in, so liquidity matters.