Transaction steps

• Authorization: The cardholder pays for the purchase and the merchant submits the transaction to the acquirer (acquiring bank). The acquirer verifies the credit card number, the transaction type and the amount with the issuer (Card-issuing bank) and reserves that amount of the cardholder's credit limit for the merchant. An authorization will generate an approval code, which the merchant stores with the transaction.

• Batching: Authorized transactions are stored in "batches", which are sent to the acquirer. Batches are typically submitted once per day at the end of the business day. If a transaction is not submitted in the batch, the authorization will stay valid for a period determined by the issuer, after which the held amount will be returned back to the cardholder's available credit (see authorization hold). Some transactions may be submitted in the batch without prior authorizations; these are either transactions falling under the merchant's floor limit or ones where the authorization was unsuccessful but the merchant still attempts to force the transaction through. (Such may be the case when the cardholder is not present but owes the merchant additional money, such as extending a hotel stay or car rental.)

• Clearing and Settlement: The acquirer sends the batch transactions through the credit card association, which debits the issuers for payment and credits the acquirer. Essentially, the issuer pays the acquirer for the transaction.

• Funding: Once the acquirer has been paid, the acquirer pays the merchant. The merchant receives the amount totaling the funds in the batch minus the "discount rate," which is the fee the merchant pays the acquirer for processing the transactions.

• Chargebacks: A chargeback is an event in which money in a merchant account is held due to a dispute relating to the transaction. Chargebacks are typically initiated by the cardholder. In the event of a chargeback, the issuer returns the transaction to the acquirer for resolution. The acquirer then forwards the chargeback to the merchant, who must either accept the chargeback or contest it.

Parties involved

• Cardholder: The holder of the card used to make a purchase; the consumer.
• Card-issuing bank: The financial institution or other organization that issued the credit card to the cardholder. This bank bills the consumer for repayment and bears the risk that the card is used fraudulently. American Express and Discover were previously the only card-issuing banks for their respective brands, but as of 2007, this is no longer the case. Cards issued by banks to cardholders in a different country are known as offshore credit cards.
• Merchant: The individual or business accepting credit card payments for products or services sold to the cardholder.
• Acquiring bank: The financial institution accepting payment for the products or services on behalf of the merchant.
• Independent sales organization: Resellers (to merchants) of the services of the acquiring bank.
• Merchant account: This could refer to the acquiring bank or the independent sales organization, but in general is the organization that the merchant deals with.
• Credit Card association: An association of card-issuing banks such as Visa, MasterCard, Discover, American Express, etc. that set transaction terms for merchants, card-issuing banks, and acquiring banks.
• Transaction network: The system that implements the mechanics of the electronic transactions. May be operated by an independent company, and one company may operate multiple networks.
• Affinity partner: Some institutions lend their names to an issuer to attract customers that have a strong relationship with that institution, and get paid a fee or a percentage of the balance for each card issued using their name. Examples of typical affinity partners are sports teams, universities, charities, professional organizations, and major retailers.

The flow of information and money between these parties — always through the card associations — is known as the interchange, and it consists of a few steps.

Benefits to merchants

For merchants, a credit card transaction is often more secure than other forms of payment, such as checks, because the issuing bank commits to pay the merchant the moment the transaction is authorized, regardless of whether the consumer defaults on the credit card payment (except for legitimate disputes, which are discussed below, and can result in charges back to the merchant). In most cases, cards are even more secure than cash, because they discourage theft by the merchant's employees and reduce the amount of cash on the premises. Prior to credit cards, each merchant had to evaluate each customer's credit history before extending credit. That task is now performed by the banks which assume the credit risk. Credit cards can also aid in securing a sale, especially if the customer does not have enough cash on his or her person or checking account.

For each purchase, the bank charges the merchant a commission (discount fee) for this service and there may be a certain delay before the agreed payment is received by the merchant. The commission is often a percentage of the transaction amount, plus a fixed fee. In addition, a merchant may be penalized or have their ability to receive payment using that credit card restricted if there are too many cancellations or reversals of charges as a result of disputes. Some small merchants require credit purchases to have a minimum amount to compensate for the transaction costs.

In some countries, for example the Nordic countries, banks guarantee payment on stolen cards only if an ID card is checked and the ID card number/civic registration number is written down on the receipt together with the signature. In these countries merchants therefore usually ask for ID. Non-Nordic citizens, who are unlikely to possess a Nordic ID card or driving license, will instead have to show their passport, and the passport number will be written down on the receipt, sometimes together with other information. Some shops use the card's PIN for identification, and in that case showing an ID card is not necessary.