Credit Card Repayment Calculator

Quick answer

Paying only the minimum on a credit card is designed to be slow: a £2,000 balance at 24.9% APR takes about 19 years to clear on minimum payments and costs around £5,502 in interest. Paying a fixed £100 a month clears it in 27 months for £611 interest.

Use the credit card repayment calculator

Pop your figures into the tool above: the outstanding balance, the card's APR (printed on every statement), and the monthly payment you can realistically make. It returns the number of months to clear the debt, the total you will repay, and the interest portion of that total. Change the monthly payment and watch the timeline and interest move.

How credit card interest actually works

Credit cards charge interest daily on the balance you carry, then add it to your account once a month. The headline number is the APR (annual percentage rate), but the card applies a smaller monthly slice of it. A clean way to picture it is:

Monthly interest = balance × (APR ÷ 12)

So a £2,000 balance on a card with a 24.9% APR attracts roughly £2,000 × (0.249 ÷ 12) = £41.50 of interest in a month. That interest is added to your balance, and next month interest is charged on the slightly larger figure. That compounding is why a balance you barely touch seems to stand still.

The reason minimum-only payments trap people is built into how the minimum is set. A typical UK minimum payment is the greater of a small percentage of the balance (often 1%) plus that month's interest and fees, or a floor such as £5. Because the percentage shrinks as the balance shrinks, your payment falls just as slowly as the debt does — you are always paying mostly interest with a sliver off the capital.

The calculator does the heavy lifting, but the formula behind a fixed monthly payment is the standard amortisation one: months = −ln(1 − r × B ÷ P) ÷ ln(1 + r), where r is the monthly rate, B the balance and P your payment. If your payment is smaller than one month's interest, the balance grows and the debt never clears — the tool will flag that.

Worked example: the cost of a steady £100 a month

Say you owe £3,000 on a card at 24.9% APR and decide to pay a fixed £100 every month. The monthly rate is 0.249 ÷ 12 = 2.075%.

• Month one interest: £3,000 × 0.02075 = £62.25. Your £100 clears that, and only £37.75 comes off the balance.
• Run that forward and it takes roughly 48 months — four years — to clear.
• You will have paid about £4,740 in total, of which around £1,740 is pure interest.

Now keep the same debt but pay only the minimum (about 1% of the balance plus interest). The balance falls by barely 1% a month, so clearing £3,000 this way can take the best part of two decades and cost more in interest than the original debt. Same card, same starting point — the only variable that changed your future is the payment.

Worked example: why a bigger payment pays off twice

Here is the lever most people underestimate. Take a £5,000 balance at 21.9% APR (monthly rate 1.842%).

Finding an extra £100 a month does not just halve the time — it saves around £1,500 in interest. That is because every extra pound goes straight at the capital, which stops interest being charged on it for all the months that follow. Overpaying a debt is one of the few guaranteed, tax-free returns you can get: clearing a 21.9% balance is effectively a 21.9% return on that money. Our compound interest calculator shows the same maths working the other way when it is in your favour.

How to clear the balance faster

• Pay a fixed amount, not the minimum. Lock in the largest monthly figure you can sustain and keep paying it even as the minimum drops. Holding £100 instead of letting it fall to £30 is what shortens the timeline.
• Use a 0% balance transfer — carefully. Moving the debt to a card with a 0% promotional period means every payment cuts the capital. Watch the transfer fee (often 2–3% of the balance) and aim to clear it before the 0% window ends, or the rate jumps to a standard APR.
• Attack the highest APR first. If you carry more than one card, throw spare cash at the most expensive one while paying the minimum on the rest. It saves the most interest mathematically.
• Stop adding new spending to a card you are trying to clear. New purchases can sit at a different rate and undo your progress.
• Consolidate only if it genuinely lowers the rate. A personal loan at a lower fixed rate can beat card interest, but check the total cost over the full term. Compare options with the debt consolidation calculator before committing.

It also helps to know where your money is going before you decide how much to throw at the card. A quick run through the budget calculator often frees up more than people expect. And because card balances feed directly into your credit utilisation, paying them down usually lifts your credit score as a bonus.

Common mistakes to avoid

• Confusing APR with the monthly rate. A 24.9% APR is not 24.9% a month — it is roughly 2.075% a month. Mixing them up makes the debt look either trivial or terrifying.
• Reading the minimum payment as a target. It is the lender's floor, set to keep you in debt for as long as the rules allow, not a sensible repayment plan.
• Ignoring the 0% expiry date. Balance transfer deals revert to a high APR the day the promotion ends. Diarise it and clear or move the balance first.
• Forgetting the transfer fee. A 3% fee on £5,000 is £150 added to your balance on day one — still often worth it, but factor it in.
• Treating card interest as tax-deductible. Interest on a personal credit card is not an allowable expense, unlike some genuine business borrowing. Don't bank on relief that isn't there.

If you are in persistent debt — the Financial Conduct Authority defines this as paying more in interest and charges than off your balance over 18 months — your lender must contact you and help you find a way forward. You can read the rules at the FCA's credit card pages, and get free, impartial help from MoneyHelper, the government-backed money guidance service.

These figures are estimates for guidance only and are not personal tax or financial advice. If your debts feel unmanageable, speak to a free debt charity such as StepChange or Citizens Advice.

Related tools to plan your repayment

Once you have a payoff date, line up the rest of your plan. Use the debt consolidation calculator to test whether one loan beats several cards, the personal loan calculator to compare a fixed-rate alternative, and the budget calculator to find the extra monthly payment that gets you debt-free sooner.

£2,000 at 24.9% APR: minimum vs fixed payments

A 0% balance transfer can pause the interest entirely (watch the transfer fee and the end date). Free help if it feels unmanageable: MoneyHelper debt help. Compare consolidation with the consolidation calculator.

Who should use this calculator

This shows what a credit card balance really costs, and it is the clearest illustration in personal finance of why minimum payments are designed against you. Paying only the minimum on a typical balance can take decades and cost more in interest than the original debt.

The reason is that the minimum is usually a percentage of the balance, so it falls as the balance falls, stretching the term almost indefinitely. Fixing your payment at a constant amount instead — even the current minimum — transforms the timeline. The calculator lets you set a target payoff period and shows what monthly payment achieves it.

What this calculator assumes

• Interest is charged monthly on the balance, compounding on anything unpaid.
• The monthly payment you set stays constant, unlike a true minimum payment which decreases.
• No further spending is added to the card.
• One-off extra payments reduce the balance immediately.

Limitations — what it does not cover

• How real minimum payments work — typically a percentage of the balance plus interest and fees, falling over time.
• Promotional 0% periods and the reversion rate afterwards.
• Balance transfers, including the transfer fee, which are usually the fastest way to cut the cost of an expensive balance.
• Payment allocation — payments must go to the highest-rate balance first, so cash advances and purchases at different rates behave in ways this does not model.
• Fees and charges for late or missed payments, and the credit-file damage they cause.
• Persistent debt rules, under which your provider must intervene if you pay more in interest and charges than principal over 18 months.