Interest starts the day your purchase posts to your account — but only if you carry a balance past your due date

Most credit cards give you a grace period, usually 21 to 25 days, between the day a purchase posts and the day interest begins to accrue. During this window, you pay no interest on that purchase, even if you haven't paid your bill yet. The catch: the grace period only works if you pay your full statement balance by the due date. If you carry any balance forward, interest starts immediately on new purchases the next day.

The exact timing depends on when your purchase posts, when your billing cycle closes, and when your payment is due. A purchase made on the first day of your billing cycle has the longest grace period. A purchase made on the last day has the shortest. But the rule stays the same: no interest during the grace period if you pay in full, and interest from day one on new purchases if you don't.

Cash advances and balance transfers work differently. Interest on cash advances usually starts the day you take the cash, with no grace period at all. Balance transfers often have a promotional period with no interest (sometimes 0% for 6 to 21 months), but after that period ends, interest accrues on any remaining balance.

Key Takeaways

  • A grace period typically lasts 21 to 25 days from when a purchase posts, during which no interest accrues if you pay your full statement balance by the due date.
  • If you carry a balance from one month to the next, interest starts immediately on all new purchases, even during what would normally be the grace period.
  • Cash advances have no grace period and begin accruing interest the moment you withdraw the cash.
  • Balance transfers may offer a promotional 0% period, but interest begins accruing on any unpaid balance once that period ends.

How the grace period actually works

The grace period is a benefit that only applies if you have been paying your full balance each month. It is not a right you keep forever — it can be lost if you miss a payment or carry a balance. Once you carry a balance, the grace period disappears for new purchases until you pay off the entire balance and return to paying in full.

Your billing cycle typically runs for about 30 days. A purchase made early in the cycle might have 50 days before interest kicks in (the rest of the cycle, plus the grace period). A purchase made near the end might have only 25 days. The card issuer's terms will tell you the exact length of your grace period, but you can count on it being at least 21 days if you have a good payment history.

The grace period clock starts when the purchase posts, not when you make it. A purchase you make on a Friday might not post until Monday, which shifts the entire timeline forward. Online and in-store purchases usually post within one business day, but some merchants take longer.

What happens when you carry a balance

Carrying a balance means you did not pay your full statement balance by the due date. Once you do this, the grace period ends for new purchases. Interest will accrue on those new purchases starting the day after they post, even though you have not yet been billed for them.

The interest rate applied is your card's APR (annual percentage rate), divided by 365 and multiplied by your daily balance. Most cards calculate interest daily and add it to your balance monthly. If your APR is 18% and you carry a $1,000 balance, you are accruing roughly $0.49 per day in interest.

The balance you carry also determines which purchases get interest. Interest accrues on the oldest balance first (the one from the previous month), then on new purchases if a balance remains. Some cards use different methods, so check your terms. The key point: once you carry a balance, you lose the grace period on new purchases until the entire balance is paid off.

Cash advances and their immediate interest

A cash advance is when you withdraw cash from your credit card at an ATM or through a bank. Unlike a purchase, a cash advance has no grace period. Interest starts accruing the day you take the cash, and it usually accrues at a higher APR than purchases.

Cash advances also typically charge a fee upfront — usually 3% to 5% of the amount withdrawn, with a minimum fee of $5 to $10. So if you withdraw $200, you might pay $6 to $10 immediately, plus interest from day one. This makes cash advances one of the most expensive ways to use a credit card.

Because of these costs, cash advances should be a last resort. If you need cash, a debit card, a personal loan, or a line of credit from your bank will almost always be cheaper.

Balance transfers and promotional periods

A balance transfer moves debt from one card to another, usually to take advantage of a lower interest rate or a promotional period. Many cards offer 0% APR on balance transfers for a set time — commonly 6 to 21 months, depending on the card and the offer.

During the promotional period, no interest accrues on the transferred balance, even if you make only minimum payments. Once the promotional period ends, the regular APR kicks in on any remaining balance. Interest accrues daily from that point forward.

Balance transfers also charge a fee, usually 3% to 5% of the amount transferred. This fee is added to your balance immediately, so it starts accruing interest (or sits interest-free during the promotional period, depending on the card's terms). Always calculate whether the fee and the eventual interest after the promotion ends are worth the savings compared to your current card.

How to avoid interest charges altogether

The simplest way to avoid interest is to pay your full statement balance by the due date every month. This keeps your grace period intact and costs you nothing in interest. If you cannot pay the full balance, pay as much as you can — every dollar you pay reduces the balance that accrues interest.

If you are carrying a balance and want to stop the interest clock on new purchases, focus on paying down the old balance first. Once the entire balance is zero, the grace period returns for new purchases. Some people set up automatic payments for the full statement balance each month, which removes the risk of forgetting the due date.

Another option is to use a card with a 0% introductory APR period on purchases. These offers typically last 6 to 12 months and give you time to pay down a balance without interest accruing. However, once the introductory period ends, the regular APR applies, so this is a tool for a specific situation, not a long-term solution.

Understanding your card's specific terms

Every card's grace period and interest rules are slightly different. Your card issuer is required to disclose the grace period length, the APR for purchases, the APR for cash advances, and the APR for balance transfers in a document called the Schumer Box (named after the law that requires it). This box appears on the card's marketing materials and on your statement.

Your cardholder agreement contains the full details: exactly when the grace period starts, how interest is calculated, what happens if you miss a payment, and whether the grace period can be lost. You can request this document from your card issuer or find it on their website. Reading it once, when you first get the card, answers most questions about how interest works on your specific card.

If you are unsure whether a purchase has started accruing interest, log into your online account or call the customer service number on the back of your card. They can tell you your current balance, your due date, and whether any interest is accruing on specific transactions.

Frequently Asked Questions

Does interest start if I only make a minimum payment?

Yes. A minimum payment is not the same as paying your full statement balance. If you pay only the minimum, you are carrying a balance, which means the grace period ends and interest accrues on new purchases from day one. Interest also accrues on the unpaid portion of your old balance.

Can I get the grace period back after I lose it?

Yes. Once you pay your entire balance down to zero, the grace period returns for new purchases. You do not have to wait for your next billing cycle — as soon as the balance hits zero, new purchases are protected by the grace period again (assuming you continue to pay in full each month).

What if my payment arrives after the due date?

If your payment arrives after the due date, you have missed the deadline. Interest will accrue on any unpaid balance, and you may also be charged a late fee. Some card issuers offer a grace period of a few days after the due date before they report the late payment to credit bureaus, but interest still accrues from the due date itself.

Does interest accrue on rewards I earn?

No. Rewards points or cash back are separate from your balance and do not accrue interest. They are credited to your account as you make purchases and can be redeemed or used to offset your balance, but they themselves do not earn or owe interest.

Why is the APR for cash advances higher than for purchases?

Card issuers charge a higher APR on cash advances because they consider them riskier — you are borrowing cash directly rather than making a purchase from a merchant. The higher rate compensates them for that risk. Additionally, cash advances have no grace period, so interest starts immediately, making them much more expensive overall.