Account Number
A unique number assigned by a financial institution to a customer. On a credit card, this number is embossed and encoded on the plastic card.

Annual Fee
Many credit card issuers charge an annual membership or participation fee. These fees usually range from $15-50, but can be as much as several hundred dollars. "No annual fee" cards are growing in popularity, and some lenders may be willing to waive this fee to keep your business.

Annual Percentage Rate (APR)
Expressed as a yearly interest rate, the APR is essentially a measure of the cost of credit. This rate may be subject to change, based on the terms of the card and whether the rate is fixed or variable. Also, you may be charged different APRs for different transactions. For example, cash advances are usually charged at a higher rate with no grace period.

Application fee
Some credit card issuers may require an "application" or "processing" fee before even considering you for a card. This is uncommon among general-use cards, but may apply to cards designed for people with new or damaged credit, such as secured, unsecured and pre-paid credit cards.

Average daily balance
This is the most common method used by credit card issuers for calculating the payment due. The average daily balance is calculated by adding each day's balance (charges minus any credits), and dividing by the number of days in the billing cycle. The average daily balance is then multiplied by the card's monthly periodic rate (the APR divided by 12) to calculate the finance charge for the month.

Adjusted balance
A less-common method for calculating monthly interest charges which favors the cardholder more than the bank-preferred "average daily balance" method. The balance is determined by subtracting payments or credits received during the current billing period from the balance at the end of the previous billing period. Purchases for the current billing period are not factored into the calculation. This way cardholders have until the end of the billing cycle to pay off portions of their balance and avoid paying interest charges on those amounts.

Automated Teller Machine
Allows you to perform banking transactions anywhere and at anytime. By using a debit or ATM card at an ATM, you can withdraw cash from checking or savings accounts, make a deposit or transfer money from one account to another. You can also get cash advances using a credit card at an ATM.

Affinity Card
A card that is offered jointly by two organizations. One is a credit card issuer and the other is a professional association, special interest group or other non-bank company.

Available Credit
The difference between the outstanding balance on your credit account and your credit limit; the amount of credit you have left. If you oversee your credit card properly, you should try to keep 15% of your Credit Limit available just in case of emergencies.

Acquirer
A bank or company that acquires data relating to transactions from a merchant or card acceptor for processing.

Acquiring Bank
A bank that receives the credit card transactions and then settles with the issuing banks. Bank that signs up / enables the merchant to process transactions.

Address Verification Service (AVS)
A method of reducing fraud in mail order/telephone order transactions by using cardholder billing address information in the authorization request.

Approval Response
An authorization response received when a transaction is approved.

Authentication
The process of assuring that data has come from its claimed source, or of corroborating the claimed identity of a communicating party.

Authorization
The act of insuring that the cardholder has adequate funds available against their line of credit. A positive authorization results in an authorization code being generated, and those funds being set aside. The cardholder's available credit limit is reduced by the authorized amount.

Authorization Amount
Dollar amount approved

Authorization Date
Date and Time that transaction was authorized

Authorization Only
A transaction created to reserve an amount against a credit card's available limit for intended purchases; the settlement may occur within three to five days, depending on the card type.

Authorized Amount
Dollar amount approved

Authorized Transactions
Transaction that has been approved