Minimum payment calculator
Paying only the minimum stretches a card over many years, because the minimum shrinks as the balance falls. Enter your balance, APR and minimum terms to see how long it takes and the interest you pay, then add an amount on top to watch the payoff line shorten. Figures assume no new spending on the card.
Worked example, illustrative only
A £3,000 balance at 23.9% APR, paid at the minimum, takes 15 years 3 months to clear and costs £4,864 in interest. Pay £50 a month on top and it clears 11 years 6 months sooner, saving £3,561. Illustrative only, not a quote or advice.
How it works
- The card's minimum is usually this month's interest and charges plus about 1% of the balance, subject to a small floor, so as the balance falls the minimum falls with it.
- Because the payment keeps shrinking, the last portion of the debt is paid off incredibly slowly, which is how a modest balance can take many years to clear.
- Almost all of an early minimum payment is interest, so the balance barely moves at the start.
- A fixed amount on top of the minimum, or fixing your payment at today's minimum rather than letting it drop, clears the card far sooner and saves a large amount of interest.
Frequently asked questions
Why does paying the minimum take so long?
The minimum is a percentage of the balance, so it shrinks every month as the balance falls. Near the end you are paying only a few pounds above the interest, so the balance creeps down very slowly. Fixing your payment at a set amount avoids this and clears the card in a fraction of the time.
How is the minimum payment worked out?
Each month this calculator takes the greater of your floor and this month's interest plus a small percentage of the balance (about 1%). That mirrors the UK rule where the minimum is the higher of interest and charges plus roughly 1% of the balance, or a small fixed amount such as £5. The exact figure varies by card, so treat this as a close, transparent approximation.
What difference does paying a little more than the minimum make?
Usually a large one. The extra goes straight onto the balance, and because the minimum is recalculated on a smaller balance each month, the gap compounds. The chart shows the payoff line shortening as you raise the amount.
What is the single best thing I can do?
Stop the minimum from shrinking. Keep paying at least the first month's minimum as a fixed amount every month, and pay more if you can. Because interest is charged on the whole balance, every extra pound of principal you clear stops future interest for the rest of the term.
Is this financial advice?
No. It is an indicative planning estimate using the figures you enter, not advice, a quote, or a credit decision. Your card's exact minimum formula, fees and any rate changes affect the real numbers.
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This calculator gives an indicative planning estimate from the figures you enter. It is not advice, a quote, or a credit decision, and CoreFi does not offer or arrange personal credit. CoreFi is a trading name of JG Core Ltd (company 16218779). Figures reviewed September 2026.