Plot No. 21 · Money & Finance
Credit Card Payoff Calculator
Work out how long a credit card takes to clear when you pay a fixed amount each month, plus the total interest you will pay. It uses the monthly interest rate from your APR and the standard payoff formula, and warns you if your payment is too small to ever clear the balance.
This assumes a fixed APR, a fixed monthly payment and no new spending or fees. Real cards may apply a percentage-based minimum that falls as the balance drops, which takes much longer.
The link saves your inputs so you can bookmark or share this exact result.
The payoff formula, worked through
Card interest is charged monthly at the APR divided by 12. For the default card, £3,000 at 21.9% APR, the monthly rate r is 21.9% / 12 = 0.01825, so the first month adds £3,000 x 0.01825 = £54.75 of interest. A £150 payment covers that and takes £95.25 off the balance.
The number of months is n = -ln(1 - B x r / P) / ln(1 + r), rounded up. Here that is -ln(1 - 3000 x 0.01825 / 150) / ln(1.01825) = 25.11, so the card clears in 26 months. The first 25 payments are the full £150 and the last one is only £16.67, which is why the total interest is £766.67 rather than 26 x £150 minus the balance. If B x r is at least P, the logarithm has no answer: the payment never gets ahead of the interest.
Months to pay off a credit card at 21.9% APR
Each cell shows the months to clear the balance at that fixed monthly payment, with the total interest underneath. "Never" means the payment does not cover the first month's interest.
| Balance | £50/mo | £100/mo | £150/mo | £200/mo | £300/mo | £500/mo |
|---|---|---|---|---|---|---|
| £1,000 | 26 mo £256 interest | 12 mo £114 interest | 8 mo £76 interest | 6 mo £59 interest | 4 mo £42 interest | 3 mo £28 interest |
| £2,000 | 73 mo £1,620 interest | 26 mo £511 interest | 16 mo £313 interest | 12 mo £229 interest | 8 mo £152 interest | 5 mo £96 interest |
| £3,000 | Never | 44 mo £1,385 interest | 26 mo £767 interest | 18 mo £538 interest | 12 mo £343 interest | 7 mo £207 interest |
| £5,000 | Never | 135 mo £8,470 interest | 52 mo £2,774 interest | 34 mo £1,738 interest | 21 mo £1,016 interest | 12 mo £571 interest |
| £10,000 | Never | Never | Never | 135 mo £16,940 interest | 52 mo £5,549 interest | 26 mo £2,556 interest |
Monthly payment needed to be debt free by a deadline
Working the other way round: pick a balance and a target, and this is the fixed payment that clears it in exactly that many months at 21.9% APR, from payment = B x r / (1 - (1 + r)^-n). Enter the figure in the calculator above to check the total interest.
| Balance | 6 months | 12 months | 18 months | 24 months | 36 months | 48 months |
|---|---|---|---|---|---|---|
| £1,000 | £177.47 | £93.55 | £65.68 | £51.83 | £38.14 | £31.45 |
| £2,500 | £443.68 | £233.87 | £164.20 | £129.57 | £95.35 | £78.63 |
| £5,000 | £887.36 | £467.73 | £328.40 | £259.14 | £190.69 | £157.26 |
| £10,000 | £1,774.73 | £935.46 | £656.80 | £518.29 | £381.39 | £314.52 |
How the APR changes the same plan
The same £3,000 balance paid off at £150 a month, at APRs from a 0% balance transfer up to a high-rate store card.
| APR | First month's interest | Time to clear | Total interest |
|---|---|---|---|
| 0% | £0.00 | 1 year 8 months | £0.00 |
| 12.9% | £32.25 | 1 year 11 months | £396.05 |
| 18.9% | £47.25 | 2 years 1 month | £631.70 |
| 21.9% | £54.75 | 2 years 2 months | £766.67 |
| 24.9% | £62.25 | 2 years 3 months | £915.95 |
| 29.9% | £74.75 | 2 years 5 months | £1,204.33 |
| 34.9% | £87.25 | 2 years 7 months | £1,560.29 |
The gap between the cheapest and dearest rows is why moving a balance to a lower rate can matter as much as paying more. The APR vs interest rate guide explains what the headline APR on a card includes.
The minimum payment trap
Here the minimum is 2.5% of the balance or £25, whichever is larger, at 21.9% APR. Because it falls as the balance falls, paying only the minimum stretches the debt out for years. Keeping the payment fixed at the first month's minimum, instead of letting it shrink, is a small change that cuts the time dramatically on larger balances.
| Balance | First minimum | Minimum only | Fixed at first minimum |
|---|---|---|---|
| £1,000 | £25.46 | 6 years 1 month, £808 interest | 5 years 10 months, £776 interest |
| £3,000 | £76.37 | 18 years 9 months, £5,873 interest | 5 years 10 months, £2,329 interest |
| £5,000 | £127.28 | 24 years 7 months, £10,938 interest | 5 years 10 months, £3,882 interest |
Card issuers set their own minimum rules, so check your statement for the exact figure. With more than one card, the debt avalanche vs snowball guide uses the same minimum rule to compare the two payoff orders, and the debt-to-income ratio calculator shows how your total repayments compare with your income.
How the credit card payoff time is worked out
This calculator finds how long a fixed monthly payment takes to clear a credit card balance. It turns the APR into a monthly rate by dividing by 12, then uses the standard payoff formula: months equals minus the natural log of one minus balance times monthly rate divided by payment, all over the natural log of one plus the monthly rate, rounded up to a whole month.
There is a catch the formula cannot ignore. If your monthly payment is no larger than the interest charged that month, the balance never falls and the card never clears. The calculator checks for this and shows a clear warning instead of a meaningless number, so you always know whether your payment is actually making progress.
How to use the credit card payoff calculator
- Enter your current balance and the card's APR.
- Enter the fixed amount you intend to pay every month.
- Read the time to clear, total interest and total paid, then raise the payment to watch the payoff time fall sharply.
Worked examples
Paying a steady amount
Inputs: 3,000 balance, 21.9% APR, 150 a month
Result: The card clears in 26 months, 2 years and 2 months. The last payment is only about 16.67, so the interest comes to about 766.67 for a total of about 3,766.67 paid.
Payment too small to clear
Inputs: 5,000 balance, 24.9% APR, 100 a month
Result: The monthly interest is about 104, which is more than the 100 payment, so the balance never clears and the calculator warns you to pay more.
Limitations and common mistakes
Edge cases and limitations
- It assumes a fixed APR, a fixed monthly payment and no new spending or fees added to the card.
- Real cards often set a percentage-based minimum payment that shrinks as the balance falls, which stretches the payoff far longer than a fixed payment.
- Months are rounded up to the next whole month, so the final real payment is usually smaller than a full instalment.
Common mistakes
- Paying only the minimum, which is mostly interest early on and can keep a balance alive for years.
- Continuing to spend on the card while paying it down, which resets progress because the formula assumes no new charges.
Frequently asked questions
How long will it take to pay off my credit card?
It depends on the balance, the APR and how much you pay each month. With a £3,000 balance at 21.9% APR paying £150 a month, it clears in 26 months (2 years 2 months) and costs £766.67 in interest. Paying more each month shortens this sharply.
What happens if my payment is too small?
If your fixed monthly payment is less than or equal to the interest charged that month, the balance never goes down and the card never clears. The calculator detects this and tells you instead of showing a misleading number. The fix is to pay more than the monthly interest.
Why does only paying the minimum cost so much?
Minimum payments are often a small percentage of the balance, so early on most of your payment is interest and the balance barely moves. Paying a higher fixed amount means more goes to the principal each month, which clears the debt far faster and cuts total interest.
How long does it take to pay off a credit card paying only the minimum?
Much longer than most people expect. With a minimum of 2.5% of the balance or £25, whichever is larger, a £3,000 balance at 21.9% APR takes 225 months (18 years 9 months) to clear and costs £5,873 in interest, because the minimum shrinks as the balance does.
How much do I need to pay to clear 5,000 in 2 years?
At 21.9% APR, a fixed £259.14 a month clears a £5,000 balance in exactly 24 months. The formula is payment = B x r / (1 - (1 + r)^-n), with r the APR divided by 12 and n the number of months. The table above gives the same figure for other balances and deadlines.
How much interest does a credit card charge per month?
Roughly the APR divided by 12, applied to the balance. At 21.9% APR that is about 1.825% a month, so a £3,000 balance is charged £54.75 in its first month. Any payment at or below that figure leaves the balance where it was.
Related calculators
UK Salary Take-Home Calculator
Estimate your monthly take-home from a UK gross salary using simplified 2026/27 tax bands.
Mortgage Repayment Calculator
See your monthly mortgage payment and total interest over the life of the loan.
FIRE Retirement Calculator
Find out when you can retire based on savings, monthly investing and target spend.
Loan Amortization Calculator
Year-by-year breakdown of principal and interest for any fixed-rate loan.
See all money & finance calculators.
Related guides
Free Bankrate credit card payoff calculator alternative
How Calc Garden's free, no-signup credit card payoff calculator compares to the Bankrate tool, with an honest feature table and where each one wins.
Debt Avalanche vs Snowball: Which Pays Off Faster?
The avalanche targets the highest APR, the snowball the smallest balance. A worked three debt example shows the interest gap and how fast each clears.
What Is a Good Debt-to-Income Ratio?
What counts as a healthy debt-to-income ratio, the exact formula, the under-36% / 37-43% / over-43% bands, and how clearing a card lowers your DTI.