The Minimum-Payment Trap: The Exact Math (2026)

Short Answer: Paying only the minimum on a $6,000 balance at 20.99% APR, under a typical "3% of the balance or $25" minimum-payment formula, takes 208 months (17 years and 4 months) and costs $7,652.97 in interest. You hand over $13,652.97 to clear $6,000 of purchases. A fixed $150 monthly payment clears the same debt in 70 months with $4,405.42 of interest, saving $3,247.55 and more than 11 years. Every number below is computed from the stated assumptions and labeled as hypothetical; check your own card agreement, because minimum-payment formulas vary by issuer.

By Finance Editorial Desk | October 1, 2026

1. What a minimum payment actually is

A minimum payment is not designed to get you out of debt. It is designed to keep the account current while the lender collects as much interest as possible for as long as possible. The two common structures, both hypothetical examples of how issuers write the rule, are:

• A percentage of the statement balance with a flat floor. Something like "the greater of 3% of your balance or $25." Outside Quebec, minimums as low as the greater of a few percent or $10 to $25 are common.
• A percentage floor set by regulation. Quebec is the only Canadian province that regulates this directly: credit card issuers must require a minimum payment of at least 5% of the outstanding balance, phased in under Bill 134 and fully in effect since August 1, 2025. That rule alone cuts years off a minimum-payment payoff compared with the rest of Canada.

Because the percentage is applied to the current balance, the payment shrinks as the balance shrinks. That one detail is the entire trap. Your payment is never a fixed plan; it is a fraction that decays, and the decay is what stretches a $6,000 balance across 17 years.

Also worth knowing: Canadian credit card statements are required to show you an estimated time to repay the balance if you make only minimum payments. If you have never read that box on your statement, read it this month. This article shows you exactly how that estimate is produced.

2. Our worked example: one household, one card (labeled hypothetical)

To keep every figure traceable, we will run the full payoff math on one hypothetical household, one time, and reuse it through the whole article:

• Starting balance: $6,000
• APR: 20.99% (monthly rate = 0.2099 / 12 = 1.749167%)
• Minimum payment rule: the greater of 3% of the current balance or $25
• No new purchases, no fees, no rate changes. A clean amortization, so the math is verifiable.

Month 1 looks like this. Interest charged: $6,000 x 0.01749167 = $104.95. Minimum payment: 3% of $6,000 = $180.00. Principal actually repaid: $180.00 - $104.95 = $75.05. New balance: $5,924.95. Read that again: of your $180 payment, $75.05 attacks the debt and $104.95 evaporates as interest. That ratio never improves until the flat floor kicks in near the end. Now let it run.

3. The full schedule: 208 months of minimums

Here is the balance, payment, and interest charge at checkpoints through the minimum-only schedule:

Totals: 208 months (17 years, 4 months), $7,652.97 in interest, $13,652.97 paid in total on a $6,000 balance.

Three things deserve your attention. First, at month 60, five years in, you still owe $2,819.41. Half the original debt remains after five years of payments. Second, the payment has fallen from $180 to $85.65 by that point, which feels like relief, but the relief is the cost: a smaller payment means a smaller principal cut, which means more months, which means more interest. Third, notice the long tail. After the $25 floor takes over around month 158, the payoff still takes another 50 months. Minimum payments end slowly, not quickly.

4. The 58.3% treadmill: why the ratio never gets better

Here is the uncomfortable mechanic hiding inside any percentage-of-balance minimum. While the payment equals 3% of the balance, the interest charged equals the balance times the monthly rate. Both are proportional to the balance, so their ratio is fixed:

Interest share of payment = (balance x 0.01749167) / (balance x 0.03) = 0.01749167 / 0.03 = 58.3%

As long as you are on the percentage minimum, 58.3 cents of every dollar you pay goes to interest, month after month, year after year. Check month 120 in the table: payment $40.25, interest $23.47. That is 58.3%. Check month 36: $67.55 / $115.86. That is 58.3%. The ratio is pinned until the flat $25 floor engages, and by then you have already paid most of the $7,652.97.

This is the single most useful mental model for minimum payments. A fixed payment attacks a growing share of principal over time because the interest charge falls while the payment stays put. A percentage minimum attacks a constant share of principal, so the treadmill runs at the same speed until the very end. The minimum is engineered to keep you in the high-interest zone as long as possible.

Generalize it: with any minimum percentage p and monthly rate r, the interest share of each percentage-based payment is r / p. A 2% minimum at 20.99% APR would hand 87.5% of every payment to interest (0.01749167 / 0.02), which is why low-percentage minimums are so punishing. A 5% minimum, as Quebec requires, drops the interest share to 35.0% (0.01749167 / 0.05). Same card, same rate, very different trap.

5. The flat floor and the slow last two years

When the balance falls below $833.33, 3% of the balance is less than $25, so the $25 floor takes over. That happens around month 158 in our example. The floor changes the dynamics, but not as helpfully as you might think.

At a balance of $800 with the $25 payment: interest is $13.99, principal cut is $11.01. At $400: interest $7.00, principal cut $18.00. The payment is finally fixed, so the interest share finally falls, but the balance is small and each month only shaves $11 to $24 off it. The last $833 of a minimum-only payoff still takes roughly 50 months. The floor is a mercy rule that arrives after the damage is done; it finishes the job, but only after 13 years of percentage minimums have extracted their price.

One more floor observation worth internalizing: a flat minimum that ignores the balance is dangerous in the other direction. Suppose the rule were a flat $25 regardless of balance, with no percentage component. Month 1 interest on $6,000 is $104.95, which exceeds the $25 payment. The balance would grow every month: $6,000 becomes $6,079.95, then $6,161.30, compounding upward forever. A payment smaller than the monthly interest charge is not a payoff plan; it is negative amortization. This is why issuers pair flat floors with percentage formulas. If your own minimum ever approaches your monthly interest charge, your balance is about to stop shrinking.

6. The floor is what actually finishes the job

Here is a detail most minimum-payment explanations skip: without the $25 floor, the 3% minimum in our example would never clear the debt at all. A pure percentage payment decays geometrically: each month removes 3% of the balance while interest adds 1.7492%, for a net shrinkage of 1.2508% of whatever is left. After 208 months of that, you would still owe $437.63, and after another 208 months you would still owe about $32. The percentage grinds the balance toward zero forever without reaching it. The flat floor is the only thing that converts an asymptote into an ending; the last 50 months of our schedule exist because the $25 floor takes over and holds the payment fixed while the balance is small.

That is also why Quebec's 5% rule matters so much. Same $6,000 at 20.99% APR, month 1 under a 5% minimum: payment $300.00, interest $104.95, principal cut $195.05. The interest share falls to 35.0% and the principal share rises to 65.0%, against 58.3% and 41.7% for the 3% minimum. Run the full schedule with the same $25 floor for comparability, and the 5% minimum clears the debt in 101 months with $3,080.04 of interest, less than half the interest and less than half the time of the 3% version ($7,652.97 over 208 months). Same card, same rate, same floor; only the percentage changed. When regulators forced the percentage up, they were buying back years of borrowers' lives with arithmetic, which tells you how much of the trap lives in that one number.

7. The same debt with a fixed $150 payment

Now the comparison that matters. Same $6,000 balance, same 20.99% APR, but a fixed $150 payment every month instead of the decaying minimum:

The fixed payment starts out smaller than the first minimum ($150 vs $180), and its first-month principal cut of $45.05 is genuinely smaller than the minimum's $75.05. Yet it finishes 11 and a half years sooner. The reason is the treadmill mechanic from section 4: the minimum's principal cut shrinks every month while the fixed payment's principal cut grows every month. By month 60, the fixed $150 is cutting $125.32 of principal per month; the minimum has decayed to an $85.65 payment, of which only $35.71 hits principal. The fixed payment compounds its progress; the minimum compounds its delay. The first payment tells you nothing about the plan. The last payment tells you everything.

8. The extra-payment ladder: what "a little more" buys

You do not have to jump from the minimum to a big fixed payment. Any extra dollar rides the same mechanics in your favor. Here is the ladder for the same hypothetical $6,000 at 20.99% APR:

Two details make this table worth studying. First, "minimum + $50" beats a fixed $150 on both time and interest (71 months and $3,286.30 vs 70 months and $4,405.42), because the extra $50 rides on top of an early minimum that starts at $180; the plan begins with $230-a-month momentum and never loses it. Second, the jump from minimum-only to minimum-plus-$50 is the single biggest marginal win on the ladder: 137 months and $4,366.67 saved for about $50 a month in year one, less in later years as the minimum decays. After that, each step buys less, but every step buys something real. The trap is a continuum, not a cliff; you climb out one extra payment at a time.

9. The first-year cost, stated plainly

In the first 12 months of minimum-only payments, our hypothetical household pays $1,176.27 in interest and reduces the balance by only $841.15 (from $6,000 to $5,158.85). More than half of everything paid in year one, about 58.3% per the treadmill math, is pure interest. Put differently: a year of minimum payments buys you less than $850 of actual debt reduction at a cost of nearly $1,180 in interest. If that ratio does not motivate a change in payment size, nothing in this article will.

10. Run your own numbers: the formulas

Everything above came from two formulas and one loop. You can reproduce any of it for your own balance and rate.

Monthly interest charge: I = balance x (APR / 12). That is the number your payment must beat before a single dollar touches principal.

Fixed-payment payoff time: with monthly rate r, balance B, and fixed payment P (where P > r x B),

n = -ln(1 - (r x B) / P) / ln(1 + r)

months. For our fixed-$150 example: r = 0.01749167, B = 6,000, P = 150. The term (r x B) / P = 104.95 / 150 = 0.6997, and n = -ln(0.3003) / ln(1.0174917) = 1.2031 / 0.01734 = 69.4, which rounds up to 70 months. Total interest is then approximately n x P - B, which gives 70 x 150 - 6,000 = $4,500; the exact figure is $4,405.42 because the final payment is smaller than $150. You can check any row of section 8's ladder with this formula.

Percentage-minimum schedules have no clean closed form because the payment changes monthly, so the honest method is the loop: each month, charge interest, compute the payment as max(percentage x balance, floor), subtract, repeat until the balance hits zero. That is how every number in this article was produced. If you want to sanity-check a calculator's answer, the ln formula above is your reference for any fixed payment, and the interest-share ratio r / p is your reference for any percentage minimum.

11. When minimum payments are the right move

Minimums have a legitimate, narrow job: keeping the account current when money is tight. A minimum payment made on time avoids late fees, penalty interest, and credit-report damage, all of which cost more than the extra interest of one minimum month. If the choice this month is the minimum or a missed payment, pay the minimum and do not feel guilty about it.

The trap is not one minimum payment. It is the plan of minimum payments: treating the minimum as a strategy rather than a stopgap. Three rules keep the stopgap from becoming the plan:

1. Never miss the minimum, even in a crisis month. The credit damage and fees dwarf the interest savings you were chasing.
2. Return to a fixed payment the next month. Write the fixed amount down now, while you are reading this, so the decision is made before next month's budget pressure arrives.
3. Pair the plan with a payoff order. Once you are paying a fixed amount above the minimums, point the extra at one debt at a time. Our companion guide compares the two standard orders, highest-rate-first versus smallest-balance-first, with worked math on both: Debt Avalanche vs Debt Snowball: Which Repayment Strategy Saves You More?.

And the emergency-fund question that always comes up: should extra cash go to debt or to savings? At 20.99% APR, every dollar put toward the balance earns a guaranteed, tax-free, risk-free 20.99% return by avoiding interest. No savings account competes with that. Keep a small cash buffer, one month of essentials is a common rule of thumb, so a surprise does not go back on the card, and aim everything else at the highest-rate balance.

12. Frequently asked questions

How long does it take to pay off a credit card paying only the minimum? It depends on your balance, rate, and your card's minimum formula, but the structure is always the same: a percentage-based minimum stretches the payoff to many years. In our worked hypothetical, $6,000 at 20.99% APR with a 3%-or-$25 minimum takes 208 months, over 17 years. Your statement's required disclosure box shows the estimate for your actual balance.

Why do minimum payments barely reduce my balance? Because most of each payment is interest. With a 3% minimum at 20.99% APR, 58.3% of every percentage-based payment is interest (the ratio is the monthly rate divided by the minimum percentage). Only 41.7% reduces principal, and the payment itself shrinks as the balance shrinks, so progress decelerates. See section 4 for the derivation.

Is it ever okay to pay only the minimum? For a single month, yes: it avoids late fees, penalty rates, and credit damage, which cost more than the extra interest. As an ongoing plan, no: the math in sections 3 and 7 shows the cost runs to thousands of dollars and a decade or more of extra payments.

Does paying more than the minimum really save that much? The ladder in section 8 says yes, and the effect is front-loaded. On our hypothetical, adding $50 to the minimum saves $4,366.67 in interest and cuts 137 months off the schedule. Early extra payments are the most powerful because they shrink the balance that all future interest is charged on.

What minimum-payment percentage does my card use? Check your cardholder agreement; common structures are a percentage of the balance (2% to 3%) with a flat floor ($10 to $25), or, in Quebec, at least 5% of the balance under provincial rules. The higher your percentage, the weaker the trap; Quebec's 5% rule exists precisely to shorten minimum-payment payoffs.

Should I consolidate instead of paying extra? Consolidation changes the rate, not the mechanics. A lower-rate loan with minimum-style small payments can still take years, and stretching the term can erase the rate advantage entirely. Run the fixed-payment formula from section 10 on the consolidation offer's actual payment and term before signing, and compare total interest, not just the monthly payment.

Where does debt payoff fit in my overall money plan? Clearing high-rate revolving debt is the highest-return, lowest-risk move in personal finance, ahead of investing. Once the balances are gone, the freed-up payment is new investing money. Our guide to the registered-account decision walks through where it should go next: RRSP vs TFSA: The Complete Canada Guide.

13. Related reading

• Debt Avalanche vs Debt Snowball: Which Repayment Strategy Saves You More? - once you commit to fixed payments above the minimum, this guide works the math on which debt to target first.
• Compound Interest Forensics - the same compounding that punishes minimum payments rewards steady saving; the math is identical with the sign flipped.
• Mortgage Amortization Calculator - fixed-payment amortization done right, and the template every debt payoff plan should copy.
• Browse all guides - calculators and explainers across finance, health, and math.