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Security is part of our practice and process
To help protect every transaction, we hold ourselves to a high standard for authorization and offer businesses and issuers fraud prevention support.
100% authorization requirement
To minimize the risk of fraud and protect profits, we require authorization on all card-present and card-not-present transactions.
Code 10: suspicious situations
If a business suspects fraud during a card-present transaction, they can call in a Code—10 authorization request to alert the issuer and protect the cardholder.
Stand-in functionality
If systems are down, we help participating issuers provide authorizations for their merchants.
Ways to detect
a fraudulent or
altered card
Chip card technology has made card-present transaction more secure. However, it’s still important to understand the security features of Discover® cards, Diners Club International® cards and others on our network to spot signs of tampering.
Need to verify a card on the spot? Call us.
To obtain an authorization or address verification, or to question the validity of a Discover card, call the Discover® Global Network Authorization Center at 1-800-347-1111.
Explore card features that prevent fraud online
Understand the card security features that help validation during card-not-present transactions.
Card Identification Data (CID)
The three-digit CID provides an additional layer of security. It ensures the cardholder possesses the card at the time of purchase.
Address Change Notification (ACN)
Merchants requesting an AVS are also sent an ACN, which indicates whether the cardholder billing address has changed in the last 45 days.
Card Verification Value (CVV)
A unique value is encoded on the magnetic stripe of the card; the issuer provides it as protection against counterfeit cards.
Address Verification Services (AVS)
To limit the risk of fraud on card-not-present transactions, we require any merchants to capture the cardholder's address for verification.
Tips to reduce chargebacks and risk
A few simple practices can help you communicate expectations to customers and protect your business from potentially costly fraud risks and chargebacks. Get a step-by-step guide for providing transparency, security and service.
Follow these steps before the transaction
Make sure your business name (common DBA) and customer service number are on customer receipts and bills
As a practice, obtain an authorization for duplicate charges or installment plans—unless otherwise stated
U.S businesses should enroll in Fraud Alerts to ensure you can receive notification if fraudulent transactions are detected
Clearly communicate all delivery charges, restocking fees or other fees
Explain return policies and offer documentation of these policies with each sale
Follow these steps during the transaction
Verify the customer's billing address electronically using our automated phone system or an Address Verification System (AVS)
Request and validate the CID (the three-digit code on the back of the card in the signature panel)
The CID can be submitted in the electronic authorization request or can be used when calling our authorization center
Note: All declined authorizations are final.
Follow these steps after the transaction
Verify the customer's name, full billing address, email and phone number by enrolling in our free fraud prevention solution, Verify+
Get a signature for each delivery and keep all delivery records
Document efforts to satisfy the customer when working on a chargeback
Respond to all chargebacks, even the small ones
Refund sales on the same card account used for purchase
Security training and resources
We invest time and resources in keeping every transaction safe.
Fraud prevention seminars
Discover sponsors a number of seminars and lectures on fraud prevention and protection. Call 1-800-347-6634 to learn more.
Fraud prevention associations
We’re members of several anti-fraud associations, including the International Association of Financial Crimes Investigators and The Fraud Reduction Committee.
Security-based solutions and resources
Secure Digital Payments
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Learn about securing digital paymentsSecure In-Store Transactions
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Learn about securing in-store transactionsSecurity and Authentication
Get comprehensive authentication solutions from a suite of security products.
Learn about security and authentication