Discover Payment Decline Code
Discover Decline Code 63: Security Violation
Category Fraud or SecurityRetry Guidance Hard Decline (Editorial Classification)By Payment Defender Editorial TeamUpdated July 17, 2026Last reviewed July 17, 2026
What Discover Decline Code 63 Means
Discover decline code 63 (Security Violation) indicates that a security violation was detected during processing.
Where the Response May Come From
Code 63 indicates a security condition, such as failed security checks, caused the issuer to decline. It reflects the issuer's security assessment of the transaction, so its records are the reference.
Common Reasons for This Response
Common causes include failed security checks or suspected tampering during processing.
Should the Merchant Retry the Payment?
Reattempting usually returns code 63 while the security condition stands; the cardholder may need to resolve it with their bank before proceeding.
Recommended Merchant Action
Do not keep retrying; ask the customer to contact their issuing bank or use a different payment method, and review your authentication data for issues.
What to Tell the Customer
Suggest the customer reach out to their issuing bank about the security check, or use a different payment method.
How to Reduce Similar Payment Failures
Reviewing authentication and security fields when code 63 appears helps distinguish integration issues from genuine issuer security holds.
Important Limitations
Decline-code meanings vary by processor, gateway, and payment environment, and issuers do not always disclose the specific reason behind a response. The retry classification on this page is Payment Defender editorial guidance, not an official network rule. Merchants should confirm handling with their processor or gateway.
Related Decline Codes
Sources and Review Information
Last reviewed July 17, 2026
Raw network-response codes are supplemental to the complete processor or gateway response. Meanings and recommended actions can vary by issuer, processor, gateway, card network, payment method, region, and merchant configuration.