Minimum Payment Credit Card Trap Calculator

Why minimum-only payments take so long

Credit-card minimum payments are usually set as a small percentage of the outstanding balance, in the low single digits, with a fixed floor below which the percentage stops applying. That structure is what stretches the timeline: as the balance falls, the percentage payment falls with it, so the slice going to principal shrinks month after month.

The threshold that decides everything is whether the payment beats the month’s interest. A card at 22% APR charges roughly 1.83% of the balance in interest each month, so a 2% minimum clears principal by a margin of about 0.17 percentage points. That margin is the entire engine of repayment, and it is why the same balance at a 2% minimum takes decades while at 3% it takes years. Card statements in some jurisdictions carry a warning box showing what a three-year payoff would cost by comparison.

How to use it

Enter the current balance, the card’s APR, and the minimum-payment percentage from the cardholder agreement. The calculator simulates the payments month by month and returns the time to pay off, the total amount paid, the total interest, the interest as a proportion of the original balance, and the payment floor it applied. Results update as you type. The currency selector at the top changes formatting throughout; the math is currency-neutral.

Worked example

Take a 5,000 balance at 22% APR with a 2% minimum. Each month the calculator adds interest, then applies the larger of 2% of the balance or the floor. The simulation runs to 80 years 8 months. Total paid across that span is 48,419.49, of which 43,419.49 is interest, or 868.39% of the amount originally owed. The floor in this case is 25.

One result surprises people: the term does not depend on the size of the balance. Because the floor scales with the starting amount, a 2,000 balance and a 10,000 balance at the same APR and the same minimum percentage both clear in 80 years 8 months. Only the money amounts differ. APR and minimum percentage set the timeline; the balance sets the scale.

How the math works

This is an iterative month-by-month simulation rather than a closed-form formula. Each month, interest equals the balance times the monthly rate, which is the APR divided by twelve. The payment equals the larger of the balance times the minimum percentage, or the floor. The next balance is the current balance plus interest minus the payment. The closed-form amortisation formula does not apply, because the payment is not fixed: it falls as the balance falls.

The floor is set at 0.5% of the starting balance, which comes to 25 on a 5,000 balance and scales proportionally from there. That keeps it currency-neutral, and it approximates the fixed cash floor card issuers commonly apply. The simulation stops at 1,200 months. When a combination of APR and minimum percentage never clears within that span, the calculator reports that rather than presenting the cap as a payoff term, since a balance that has not cleared has no payoff term to report.

Where the inputs come from

The balance is on the most recent statement. The APR is the purchase APR in the cardholder agreement, which is separate from balance-transfer and cash-advance APRs and is often lower than both. The minimum-payment percentage is set out in the agreement and restated on each statement. Some agreements pair a percentage with a fixed floor; others use a formula such as interest plus a small principal percentage, or a flat cash amount. What issuers must disclose, and how, is set by consumer-credit law where the card was issued, which is why the figures differ by country and why the agreement itself is the authoritative source for any specific card.

What this calculator doesn’t capture

The model holds its assumptions constant: one APR throughout, no new spending on the card, no fees beyond the stated interest, and a percentage-plus-floor minimum formula. Real accounts can carry a penalty APR after a missed payment, late fees, balance-transfer and cash-advance segments at separate rates, promotional rates that expire, and insurance products added to the statement.

The proportional floor is also a simplification at the small end. On a starting balance of a few hundred, 0.5% comes to little more than one unit of currency, well below the cash minimum an issuer would actually charge, so the simulated term runs far longer than a real account would. The output works as a baseline that shows the structural problem with minimum-only payments, not as a prediction for a specific account.

Even small overpayments compress the timeline

The arithmetic is sensitive to how much principal comes off each month, and anything paid above the minimum lands on principal in full. On the default figures, adding 25 a month alongside the minimum takes the term from 80 years 8 months to 13 years 3 months, and the interest from 43,419.49 to 7,455.47. Doubling that to 50 a month brings it to 7 years 5 months and 4,138.06 in interest. The Credit Card Payoff Calculator on this site models a fixed monthly payment directly and can show that scenario in full.