UK Credit Card Repayment Calculator

How the UK Credit Card Repayment Calculator Works

Our UK credit card repayment calculator shows you exactly how long it will take to clear your credit card balance and how much interest you will pay along the way. Enter your current balance, your card's APR, and either a fixed monthly payment or the minimum payment percentage. The calculator produces a month-by-month amortization schedule so you can see every payment split between interest and principal, right through to a zero balance.

How Credit Card Interest Is Calculated

UK credit cards charge interest daily, based on your outstanding balance. The annual percentage rate (APR) is converted to a daily rate by dividing by 365, and interest is applied each day on what you owe. For simplicity, this calculator compounds interest monthly using the formula:

Monthly Interest = Balance × (APR ÷ 12 ÷ 100)

Each month, your payment first covers the interest accrued, and the remainder reduces the principal balance. As the balance shrinks, the interest portion of each payment falls and more of your money goes towards clearing the debt — but only if you keep your payment amount fixed. If you only pay the minimum, your payment shrinks alongside the balance, which is why minimum payments can stretch a modest debt over decades.

The Minimum Payment Trap

Most UK credit card providers set the minimum payment at around 1% of your outstanding balance plus that month's interest, or a fixed floor of £25 — whichever is higher. While this keeps your immediate outgoings low, it is designed to keep you in debt for as long as possible. Consider a £3,000 balance on a card charging 21.9% APR. If you only ever pay the minimum (1% plus interest, £25 floor), it can take over 27 years to clear the balance and cost more than £4,000 in interest — more than the original debt itself. The FCA requires statements to show this warning, and for good reason.

By contrast, fixing your payment at £150 a month on the same balance clears the debt in around 24 months with roughly £700 in total interest. That is a saving of over £3,000 in interest and 25 years of debt. The single most effective thing you can do to escape credit card debt is to fix your monthly payment at the highest amount you can afford and never let it fall.

Strategies to Pay Off Your Credit Card Faster

• Fix your payment: Stop paying the minimum. Set a standing order for a fixed amount above the minimum and leave it there even as the balance falls. Every extra pound goes to principal.
• Use a 0% balance transfer: Many UK cards offer 12–30 month interest-free balance transfers for a fee of 2–3%. During the promotional window, 100% of your payment reduces the balance. Re-run this calculator with 0% APR to see the difference.
• The avalanche method: If you have multiple cards, pay the minimum on all of them and direct every spare pound to the card with the highest APR. Once that is cleared, move to the next highest.
• The snowball method: Alternatively, clear the smallest balance first for a psychological win, then roll that payment into the next smallest. This costs slightly more interest but keeps motivation high.
• Round up payments: If your fixed payment calculation comes to £137, round up to £150. Small increases at the start of a repayment schedule have an outsized impact on total interest.
• Review your APR: A card charging 24% APR versus one at 18% makes a significant difference over a long repayment. A balance transfer or a call to your provider to request a lower rate can cut your interest cost substantially.

What the Warning Means

If the calculator shows a warning that your repayment will take a long time, it means your monthly payment is barely covering the interest — or not covering it at all. When your payment is lower than the monthly interest charge, the balance grows rather than shrinks, and the debt can never be cleared. In this case the calculator will flag that the balance is increasing and suggest you raise your monthly payment above the interest-only threshold. As a rule of thumb, your monthly payment should be at least 2–3% of your balance to make meaningful progress, and ideally much more.

Typical UK Credit Card APRs

UK credit card APRs vary widely depending on the card type and your credit profile. As a guide: balance transfer cards typically charge 18–22%, purchase cards 20–24%, rewards and cashback cards 22–28%, and credit-building cards for those with thin or impaired credit files can exceed 35%. The representative APR advertised is the rate offered to at least 51% of successful applicants, so you may be offered a higher rate depending on your circumstances. Always check the APR on your statement rather than relying on the headline rate.

What This Calculator Does Not Include

• New spending: This tool assumes no further purchases on the card. Any new spending will extend the repayment time and increase interest.
• Cash advances: Withdrawals typically attract a higher APR and interest from day one with no interest-free days.
• Late payment fees: Missing a payment can add a £12 fee and trigger a higher penalty APR.
• Balance transfer fees: 0% deals usually charge a 2–3% transfer fee, which is added to your balance.
• Interest-free periods: Some cards offer up to 56 days interest-free on purchases if you pay the statement balance in full each month.