An introductory APR (also called a promo or intro rate) is a reduced interest rate — frequently 0% — offered for a limited time when you open a new card or, in some cases, complete a balance transfer. It's a marketing tool to win new customers, and it's always temporary by design.
What happens on day one after it expires
Once the intro period ends, any remaining balance starts accruing interest at the card's standard purchase APR — which the issuer discloses when you apply but which is easy to overlook. That standard rate can be considerably higher than what you'd find on a card without a promotional gimmick.
Some cards apply deferred interest, not just a new rate
A small number of promotional offers — especially retail financing — use deferred interest, where if you don't pay the full balance by the deadline, you owe interest retroactively on the entire original amount, not just the remaining balance. Read the offer terms carefully to know which type you have.
How to use an intro APR without getting burned
- Divide your balance by the number of promo months to calculate the payment needed to hit zero before it ends.
- Set a calendar reminder a month before the promo expires, not the day it does.
- Avoid new purchases on the same card if you're using the promo period to pay down an existing balance.
