Annual percentage rate (APR) — The APR is a measure of the cost of credit, expressed as a yearly interest rate. It must be disclosed before your account can be activated, and it must appear on your account statements. The card issuer also must disclose the “periodic rate” — the rate applied to your outstanding balance to figure the finance charge for each billing period.
Some credit card plans allow the issuer to change your APR when interest rates or other economic indicators — called indexes — change. Because the rate change is linked to the index’s performance, these plans are called “variable rate” programs. Rate changes raise or lower the finance charge on your account. If you’re considering a variable rate card, the issuer also must tell you that the rate may change and how the rate is determined.
Before you become obligated on the account, you also must receive information about any limits on how much and how often your rate may change.
Grace period — The grace period is the number of days you have to pay your bill in full without triggering a finance charge. For example, the credit card company may say that you have 25 days from the statement date, provided you paid your previous balance in full by the due date. The statement date is on the bill.
The grace period usually applies only to new purchases. Most credit cards do not give a grace period for cash advances and balance transfers. Instead, interest charges start right away. If your card includes a grace period, the issuer must mail your bill at least 14 days before the due date so you’ll have enough time to pay.
Annual fees — Many issuers charge annual membership or participation fees.Some card issuers assess the fee in monthly installments.
Transaction fees and other charges — Some issuers charge a fee if you use the card to get a cash advance, make a late payment, or exceed your credit limit. Some charge a monthly fee if you use the card — or if you don't.
Customer service — Customer service is something most people don’t consider, or appreciate, until there’s a problem. Look for a 24-hour toll-free telephone number.
Unauthorized charges — If your card is used without your permission, you can be held responsible for up to $50 per card. If you report the loss before the card is used, you can’t be held responsible for any unauthorized charges. To minimize your liability, report the loss as soon as possible. Some issuers have 24-hour toll-free telephone numbers to accept emergency information. It’s a good idea to follow-up with a letter to the issuer — include your account number, the date you noticed your card missing, and the date you reported the loss.Keep a record — in a safe place separate from your cards — of your account numbers, expiration dates, and the telephone numbers of each card issuer so you can report a loss quickly.
From - Federal Trade Commission, Consumer Information, Credit, Debit, and Charge Cards
