A purchase APR is the interest rate that applies to purchases made with a credit card. It is the rate of interest that the credit card company charges on purchases if you carry a balance on the card. If you pay off your full statement balance on time each month, you can avoid paying any interest on those purchases. The purchase APR is expressed as a percentage and is applied to any credit card purchases that aren’t paid off in full before the credit card grace period ends. Most credit cards have several APRs attached, and different rates for purchases and cash advances are common. The purchase APR is an important number to keep in mind if you plan to carry a balance on a credit card, as it can make a huge difference in how much interest you’ll pay over time. Credit card companies are required by law to disclose the purchase APR associated with each credit card, and every credit card’s website contains a link to that card’s cardholder agreement document.