Discover Reason Code AT: Authorization Noncompliance

What Discover Reason Code AT Means

Discover reason code AT — Authorization Noncompliance is issued when Discover determines that a transaction was not properly authorized before being submitted for settlement. Authorization is the issuer's approval for a specific transaction amount at a specific time. Without a valid authorization, the merchant has no protected right to collect the funds.

AT chargebacks arise from four primary scenarios: no authorization obtained (the merchant settled without requesting authorization); authorization declined but transaction processed anyway; authorization amount mismatch (the settled amount is materially higher than the authorized amount without an incremental authorization); or expired authorization (the authorization was obtained but the transaction wasn't cleared within the validity window, typically 7 days for Discover).

Cross-Network Equivalent Codes

Common Trigger Scenarios

• Forced post / offline processing. A POS system processes a transaction in offline mode (e.g., during a network outage) and later submits it for clearing without ever receiving an authorization approval code.
• Declined authorization, transaction completed. The card is declined at the terminal but the cashier or manager overrides the system and processes the sale anyway — either to avoid a confrontation or due to a misunderstanding of the decline.
• Incremental charges without re-authorization. A hotel, rental car company, or restaurant adds charges (resort fees, fuel charges, tips) that push the total above the authorized amount without obtaining an incremental authorization.
• Delayed shipment expiring authorization. An ecommerce merchant authorizes at checkout but delays fulfillment by more than 7 days. By the time the transaction clears, the authorization has expired.
• Recurring billing with stale authorization. The authorization for a recurring charge is not re-obtained for each billing cycle, leaving the original authorization used for a new charge period.

Key Deadlines & Timeframes

Evidence You Will Need

• Authorization approval record — Your processor's authorization log showing the approval code, authorized amount, authorization date/time, and the card number last four. This is the primary evidence for winning AT.
• Processor settlement record — Show that the settled amount matches the authorized amount (or that incremental authorizations cover the difference).
• Incremental authorization records — For hospitality, rental, or any transaction type where the final amount may exceed the initial authorization, provide each incremental authorization approval code and amount.
• Re-authorization confirmation — If you re-authorized before clearing a delayed transaction, provide the new authorization approval record showing it was obtained within the validity window.
• Transaction timeline — A simple table showing the original authorization date, the amount, the re-authorization date (if applicable), and the settlement date, demonstrating compliance with the 7-day rule.

How Merchants Lose This Dispute

• No approval code in records. If your processor records don't show an authorization approval code for the transaction, you cannot win AT. The chargeback exists precisely because of the missing authorization.
• Authorization declined, transaction completed. There is no winning a chargeback where the authorization was explicitly declined. Completing a declined transaction is a fundamental violation.
• Amount mismatch without incremental auth. If the settled amount exceeds the authorization and you cannot produce incremental authorization records covering the difference, you lose for that excess amount.
• Authorization obtained but expired. An approval code from 10 days ago doesn't protect a transaction cleared today. The authorization must be valid at the time of clearing.
• Submitting proof of delivery instead of authorization records. AT disputes are about authorization mechanics, not whether goods were delivered. Delivery proof is irrelevant to the authorization noncompliance claim.

Response Framework Overview

An AT response is technical and document-driven. Keep the rebuttal letter brief and focused on dates, amounts, and approval codes — the reviewer is checking authorization mechanics, not narrative.

1. Provide the authorization approval record. Show your processor's authorization log with a valid approval code, correct amount, and authorization date within the validity window.
2. Confirm settlement match. Show the settled amount equals the authorized amount (or that incremental authorizations account for any increase).
3. Include a transaction timeline summary. A one-page table showing authorization → re-authorization (if needed) → settlement, with all dates within required windows.

Prevention Tips

• Never process a declined authorization. If authorization is declined, stop the transaction. No amount of customer pressure justifies processing on a decline — it creates a guaranteed chargeback.
• Authorize at the latest practical moment. For ecommerce, authorize at shipment rather than checkout to minimize the authorization age at clearing. For pre-orders, authorize when fulfillment is imminent.
• Implement re-authorization workflows for delayed fulfillment. Any order that won't ship within 5 days of checkout should have a re-authorization step built into your fulfillment system.
• Use incremental authorization for variable-amount transactions. Hotels, car rentals, and restaurants with variable totals must implement incremental authorization capabilities to cover final amounts above the initial estimate.
• Audit your offline processing queue regularly. Review any transactions processed in offline mode before they are submitted for clearing. Verify each has a valid approval code or re-authorize before submitting.
• Monitor your authorization-to-settlement time metrics. Set up an alert for any transaction where authorization age at clearing exceeds 5 days, giving you time to re-authorize before the 7-day limit.

Frequently Asked Questions

What is Discover reason code AT?

Discover AT (Authorization Noncompliance) is filed when a transaction was processed without a valid authorization — missing auth, declined auth processed anyway, amount mismatch, or expired authorization at settlement time.

How do I win a Discover AT chargeback?

Provide your authorization approval record showing an approval code, the authorized amount matching the settled amount (or incremental authorizations covering the difference), and the authorization date within the validity window.

What is the response deadline for Discover AT?

20 calendar days from the chargeback notification. Missing this deadline results in automatic loss.

What is Discover's authorization validity period?

Standard Discover transactions must be cleared within 7 days of authorization. Clearing after this window results in an expired authorization, triggering AT chargeback eligibility.

Related Codes & Resources