Credit Card Interest Explained

The grace period

Most cards give you a 21–25 day grace period between the statement closing date and the due date. If you pay your full statement balance by the due date, you owe no interest — full stop.

Pay even $1 less than the full statement, and you typically lose the grace period for the next cycle: interest starts accruing immediately on new purchases until you pay the balance in full for two consecutive months.

How daily interest actually works

Each day, the card adds a tiny amount of interest based on your balance:

• Daily rate = APR ÷ 365
• At a 22% APR, the daily rate is about 0.0603%
• On a $5,000 balance, that's about $3.02 of interest added today
• Tomorrow's interest is calculated on $5,003.02, not $5,000

Over a year, that compounding daily turns the stated APR into an effective rate slightly higher than 22%.

Why minimum payments are a trap

Minimum payments are engineered to keep you in debt as long as possible while staying technically current. They are the bank's most profitable customer.

Different APRs on the same card

• Purchase APR (typical: 18–28%)
• Balance transfer APR (often promotional 0% for 12–21 months, then ~22%)
• Cash advance APR (typically 26–30%, no grace period)
• Penalty APR (triggered by late payment, often 29.99%)

Cash advances are particularly brutal: interest starts the day you take the money, with no grace period, plus a 3–5% upfront fee.

How to escape credit card interest

1. Stop using the card. Cut up if needed; you can't outrun new charges.
2. Pay as much over the minimum as you can — every extra dollar saves multiples in interest.
3. Consider a 0% balance transfer card to pause interest for 12–21 months.
4. Consider a personal loan at 8–14% to refinance card debt at a lower rate.
5. Use the avalanche method: attack the highest-APR card first while paying minimums on others.

Use the calculator