Offset Mortgage Calculator

Wondering how much your savings could save you on your mortgage? This calculator shows you exactly that. Enter your mortgage balance, interest rate, term and the savings you would offset, and you will see how much interest you could save, how much sooner you could be mortgage-free, and how keeping savings in the account longer changes the picture. For a plain English explanation of how offsetting works and who it suits, read our guide: Offset Mortgages Explained.

Aspect Mortgages — Offset Mortgage Calculator
Aspect MORTGAGES
Offset Mortgage Calculator
Setup
Your Mortgage & Savings
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yrs
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Use the saving to
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This models savings you keep adding to the linked offset account over time. The more you hold in offset savings, the less mortgage interest you are charged.
Summary
Your Offset Saving
Interest Without Offset
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Interest With Offset
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Total Interest Saved
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Outcome
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Visualisation
Interest Saved Over Time
Projection Table
Year-by-Year Breakdown
View

Important: This calculator is for illustration purposes only and does not constitute financial advice. Savings shown are based on the figures you enter, with mortgage interest calculated each month on your outstanding balance less your offset savings, at a constant annual rate. Actual savings will vary depending on the lender's terms, how interest is calculated and compounded, any product fees, and how long your savings remain in the offset account. Offset mortgage rates are sometimes higher than standard mortgage rates, so the benefit depends on your individual circumstances. This tool does not account for product fees, Early Repayment Charges, or changes in interest rates over time.

Frequently Asked Questions

How does an offset mortgage save me money?

Your linked savings are set against your mortgage balance, so interest is charged only on the difference. A £200,000 mortgage with £30,000 offset means you pay interest on £170,000. Because less interest is charged, more of each payment clears the balance, which can shorten your term or reduce your monthly payment. The calculator above shows the effect based on your own figures.

Is it better to offset or to overpay my mortgage?

Both reduce the interest you pay, but offsetting keeps your money accessible. An overpayment is normally locked into the mortgage, whereas offset savings can usually be withdrawn whenever you need them. If access to your money matters, offsetting often wins. If it does not, a lower-rate standard mortgage with overpayments may cost less overall. We can compare both for you.

Should I reduce my term or my monthly payments?

That is your choice, and the calculator lets you see both. Keep your payments the same and the saved interest shortens your term, clearing the mortgage sooner. Lower your payments instead and you free up monthly cash flow while keeping the original term. Neither is automatically better; it depends on your priorities.

Does the calculator account for higher offset rates?

The tool calculates your interest saving on the figures you enter. Because offset deals can carry a slightly higher rate than the cheapest standard products, the real question is whether the interest saved outweighs any difference in rate. That is the comparison we run for you in real figures when you speak to an adviser.

Will my savings still earn interest if I offset them?

No. Offset savings do not earn interest of their own. Instead, they reduce the interest charged on your mortgage. For higher and additional-rate taxpayers this is often more valuable than taxable savings interest, because the benefit is effectively tax-free. We can help you weigh this against your tax position.

Is an offset mortgage right for me?

Offsetting tends to suit people who hold meaningful savings and want to keep them accessible, including higher-rate taxpayers, the self-employed, and company directors holding tax reserves. The best way to know is to talk it through. See our offset mortgage advice page or speak to one of our advisers.

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There will be a fee for mortgage advice. The precise amount will depend upon your circumstances but we estimate that it will be £495 for a residential/buy to let mortgage or £1495 for an equity release/retirement mortgage.

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