UK Debt Calculator

A UK debt calculator works out how long a debt takes to clear from three numbers: your balance, its interest rate (APR), and what you pay each month. Enter them below to see your debt-free date, the total interest you'll pay, and how much faster the debt clears when you pay more. Everything runs in your browser — no sign-up, and your figures never leave your device.

Your debt

Balance owed (£)

The amount outstanding on the card, loan or overdraft.

Interest rate — APR (%)

Average UK credit card purchase rate is around 24.7%.

Monthly payment (£)

What you can pay toward this debt each month.

Pre-filled with the average UK credit card balance (£2,601, ClearScore 2025) at a typical rate — overwrite all three with your own figures.

Enter your balance, interest rate and monthly payment above, then press Calculate to see how many months your debt will take to clear, your debt-free date, and the total interest you'll pay.

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Debt-free in

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Total interest paid

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Total you'll repay

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Have several debts? Use the full debt repayment calculator

How to use this UK debt calculator

Enter three figures — your balance, the interest rate (APR) on the debt, and the monthly payment you can make — and the calculator projects the debt forward month by month until it clears. It adds interest each month, subtracts your payment, and repeats, so the result reflects how UK cards, loans and overdrafts actually work. You'll see the number of months to clear the debt, your debt-free date, and the total interest you'll pay on the way.

The most powerful number to experiment with is the monthly payment. Because interest is charged on whatever is still outstanding, every extra pound you pay goes straight at the balance and compounds in your favour. Nudge the payment up by £25 or £50 and watch the debt-free date jump forward — it's often the difference between years and months.

Why paying only the minimum costs so much

On a credit card, the minimum payment is deliberately low — typically interest, fees and charges plus 1% of the balance. At an average UK rate of around 24.7%, that means most of a minimum-only payment services interest rather than clearing the debt, which is why a mid-sized balance can take well over a decade to pay off. Paying a fixed amount each month, rather than a shrinking percentage, is what breaks that cycle. If you want to see the minimum-only trap in detail, the credit card minimum payment calculator shows the full cost.

One debt or several?

This tool focuses on a single debt, which is ideal for one card, loan or overdraft. If you're juggling several, the order you clear them in starts to matter. The debt repayment calculator handles all your debts together and shows a combined debt-free date, while the debt snowball (smallest balance first) and debt avalanche (highest interest first) calculators let you compare the two proven strategies side by side. To free up more to pay each month, the budget builder finds your real monthly surplus.

When a calculator isn't the answer

If your payment barely covers the interest, or you can't meet the minimums on your debts, a calculator isn't the right starting point — free, regulated debt advice is. StepChange, National Debtline and Citizens Advice give confidential advice at no cost, and a debt management plan or another formal option may suit you better than a self-managed payoff. In England and Wales, the Breathing Space scheme can freeze most interest and enforcement for 60 days while you get advice. There is never any need to pay a company for help you can get for free.

Frequently asked questions

What is a UK debt calculator?

A UK debt calculator is a free tool that works out how long a debt will take to clear based on your balance, its interest rate (APR) and how much you pay each month. Enter those three figures and it shows the number of months to become debt-free, your debt-free date, and the total interest you'll pay. It runs in pounds and applies interest monthly, the way UK credit cards, loans and overdrafts do.

How long will it take to pay off my debt?

It depends on your balance, your interest rate and how much you pay each month. The more you pay above the interest charged each month, the faster the balance falls — paying only a little over the interest can stretch a debt out for many years, while a modest increase can cut that to a fraction. Enter your figures above to see your exact debt-free date, then try raising the monthly payment to see the difference.

Is this debt calculator free and private?

Yes. It's completely free, needs no sign-up or email, and runs entirely in your browser — your figures never leave your device and are not sent to any server. You can use it as many times as you like to compare different payments and interest rates.

Can I use this to work out several debts at once?

This calculator handles one debt at a time, which is ideal for a single card, loan or overdraft. If you have several debts and want to see a combined debt-free date, the order to clear them in, and how each cleared payment rolls onto the next, use our multi-debt debt repayment calculator, or the debt snowball and debt avalanche calculators to compare strategies.

What if my payment doesn't cover the interest?

If your monthly payment is less than the interest added each month, the balance never goes down and the debt is not affordable on that payment — the calculator will tell you rather than show a misleading result. If you cannot pay more than the interest, that is a sign to get free, impartial debt advice from StepChange, National Debtline or Citizens Advice. In England and Wales, the Breathing Space scheme can freeze most interest and enforcement for 60 days while you get advice.

Disclaimer: This calculator is for informational purposes only and does not constitute financial advice. Results are estimates based on the figures you enter and assume a fixed interest rate and a consistent monthly payment. You remain responsible for meeting every minimum payment. If you are struggling with debt, contact a free UK debt advice service such as StepChange (stepchange.org) or National Debtline. For personal advice, consult an adviser regulated by the Financial Conduct Authority (FCA).

How this calculator works

The method

This UK debt calculator uses standard amortisation on a single balance. Each month it adds interest (the balance multiplied by the annual rate divided by twelve), then subtracts your monthly payment, repeating until the balance reaches zero. From that it works out how many months the debt takes to clear, your debt-free date, and the total interest you pay along the way. If your payment does not cover a month's interest, the balance never falls — the calculator flags this rather than returning a misleading figure. For several debts at once, use the multi-debt debt repayment calculator, which rolls each cleared payment onto the next debt.

Assumptions & limitations

The interest rate and monthly payment stay the same for the whole term unless you change the inputs.
Interest is applied monthly on the outstanding balance; it does not model daily interest, annual fees, promotional-rate expiry or missed payments.
Results are estimates to help you plan and compare, not an offer or a statement from your lender.

Data sources

Every calculation runs in your browser on the balances and rates you enter, so the results reflect your own figures. The approach follows standard UK personal-finance conventions; for reference figures and guidance we point to MoneyHelper and the Bank of England. Figures and rules change over time — always check the original source.

Built and reviewed by a UK Chartered Mechanical Engineer. More on our methodology.

Methodology & trust

Written and reviewed by Peter Barclay, a UK Chartered Mechanical Engineer — who builds and maintains these tools, pairing engineering-mathematics training with a focus on the mechanics of debt repayment. The calculators use standard amortization formulas and fixed repayment orders. Read our methodology or more about the author.

DebtSnowball is not a financial adviser and is not authorised or regulated by the FCA (Financial Conduct Authority). These tools are for education and information only, not financial advice. If you are struggling with debt, get free, impartial help from StepChange, National Debtline or Citizens Advice.

Last reviewed: September 2026 Spotted an error? Report it and we will fix it.