In the Walmart supply chain, accuracy and visibility are critical. To ensure smooth product flow into distribution centers (DCs) and fulfillment centers (FCs), Walmart requires suppliers to provide an Advance Ship Notice (ASN) before goods arrive at a facility.
An ASN, also known as EDI 856, has become a cornerstone of Walmart's Supplier Quality Excellence Program (SQEP). Suppliers who fail to provide complete and timely ASNs not only disrupt Walmart's receiving process but also risk incurring compliance penalties.
This guide explains what an ASN is, why it is required, how to set it up, and the best practices suppliers should follow to stay compliant.
What is Walmart ASN?
An Advance Ship Notice (ASN) is an electronic document that details the contents of a shipment before it reaches Walmart. It includes information such as:
- Purchase order numbers.
- Item identifiers (UPC, GTIN, etc.).
- Quantities and units of measure.
- Packaging hierarchy (cartons, pallets, SSCC-18 labels).
- Ship-from and ship-to details.
The ASN is transmitted as an EDI 856 document through Walmart's EDI network. Once submitted, it undergoes validation checks. If successful, Walmart systems can use the data to plan labor, streamline receiving, and update inventory.
Why is the ASN Important?
Submitting a valid ASN is not just a compliance requirement; it provides tangible benefits to both Walmart and suppliers.
For Walmart:
- Improves visibility into incoming freight.
- Increases efficiency in receiving operations.
- Enhances inventory accuracy and availability for customers.
For Suppliers:
- Faster purchase order matching and invoice payment.
- Reduced errors and disputes related to shipments.
- Improved product traceability in the event of recalls.
- Lower risk of SQEP penalties for non-compliance.
Ability to prioritize perishable shipments for freshness and waste reduction.
Walmart ASN Requirements
1 Timeliness
- The ASN must be accepted by Walmart before the trailer or shipment gates at the DC or FC.
- Any validation errors must be corrected and the ASN resent prior to arrival.
2 Accuracy
- All purchase order lines must be included in the ASN.
- Item numbers on the ASN must match what is physically shipped.
- Quantities submitted in the ASN must align with what Walmart receives.
3 Completeness
- The ASN must include all fields defined in Walmart's ASN mapping guides.
- Suppliers must monitor acknowledgement and error reports (997 and 824) to ensure successful transmission.
⚠️ Failure in any of these areas can result in SQEP charges under the defect type "ASN Not Downloaded."
Setting Up ASNs with Walmart
Suppliers can choose from several methods to transmit ASNs, depending on shipment volume and operational complexity.
1. AS2 Connection
Recommended for high-volume suppliers exchanging thousands of documents per year.
- Requires mapping to Walmart's ASN specifications.
- Testing must be completed through the Global Enterprise Mailbox (GEM) in Retail Link.
- Production status is granted after approval from Walmart EDI support.
2. Walmart WebEDI
A web-based solution available in Retail Link, suitable for small suppliers or as a backup method.
- No mapping or testing required.
- ASN data is entered manually by the supplier.
- Limited to POs, invoices, and ASNs (DSDC shipments are not supported).
- Free of charge, but not scalable for high volumes.
3. EDI Provider or VAN
Suppliers may contract a third-party EDI provider to manage ASN transmissions.
- The supplier provides Walmart ASN specifications to the provider.
- Many Walmart-approved providers can bypass testing.
- EDI support will establish trading partner relationships.
4. Third-Party Logistics (3PL)
Some suppliers rely on 3PLs to ship and transmit ASNs on their behalf.
- Suppliers remain fully accountable for compliance.
- Set up requires supplier-initiated requests with Walmart EDI support.
- Mapping, testing, and trading partner setup must be completed before production.
Monitoring ASN Compliance
Sending an ASN is not enough; suppliers must confirm that Walmart has successfully received and accepted it.
Step 1: Review EDI 997 Acknowledgements
- Confirms whether Walmart's system has ingested the ASN.
- Rejections must be corrected and resent before delivery.
Step 2: Monitor EDI 824 Application Advice
- Identifies data or business rule errors.
- Errors result in rejection and must be fixed immediately.
- Warnings indicate non-critical issues but should be corrected proactively.
Step 3: Use the ASN Dashboard
- Access via Retail Link > Apps > Advance Ship Notice Dashboard.
- Provides visibility into ASN submissions, quantity mismatches, and missing ASNs.
Step 4: Track in the SQEP Dashboard
- Identifies compliance issues tied to SQEP penalties.
- Essential for measuring ongoing ASN performance.
Serialized Shipping Container Code (SSCC-18)
Walmart requires all shipments to be labeled with SSCC-18 barcodes, as outlined in the Walmart Supply Chain Standards. The SSCC-18 ensures pallet and carton-level traceability, which supports labelless receiving and efficient inventory management.
Suppliers can access the latest Supply Chain Standards, including SSCC requirements, through the Packaging article in Retail Link Academy.
Best Practices for Suppliers
- ✓ Transmit ASNs immediately after shipment loading to allow time for corrections.
- ✓ Always validate data against the Walmart ASN mapping guides.
- ✓ Maintain WebEDI access as a backup to your primary EDI method.
- ✓ Review 997 and 824 messages daily to identify errors.
- ✓ Correct and retransmit errors before the shipment arrives.
- ✓ Use ASN and SQEP dashboards regularly to monitor compliance trends.
Penalties for Non-Compliance
Walmart enforces ASN compliance through SQEP. Common penalty scenarios include:
- ASN Not Downloaded: No valid ASN submitted for a purchase order.
- ASN Late: ASN submitted after gate-in at the DC or FC.
- ASN Inaccurate: Mismatched items or quantities.
Penalties are applied at the purchase order header level and can accumulate quickly if suppliers do not monitor compliance.
How iNymbus Simplifies ASN Deduction Management
For many suppliers, ASN-related chargebacks create a constant cycle of disputes and manual workload. Even small errors in timing, accuracy, or completeness can generate deductions that require significant back-office effort to resolve.
iNymbus offers an automated deduction management platform powered by Robotic Process Automation (RPA). The system is designed for high-volume suppliers and supports more than 40 major retailers, including Walmart. By automating claim disputes and documentation handling, iNymbus helps suppliers recover revenue while reducing administrative overhead.
What Sets iNymbus Apart
Automated claim processing
- Manages the dispute process end-to-end, from downloading deductions to submitting disputes with supporting documentation.
Document collection
- Gathers ASNs, proof of delivery, carrier files, and EDI acknowledgments automatically.
Retailer-specific rules
- Applies dispute logic tailored to each retailer's requirements for higher recovery accuracy.
Actionable insights
- Provides reporting on recurring ASN issues, helping suppliers identify and resolve underlying causes.
Custom workflows
- Flexible setup adapts to internal processes, approval structures, and compliance needs.

FAQs About Walmart ASN
1. Do all suppliers need to send ASNs?
Yes. All suppliers shipping to Walmart U.S. DCs and FCs must send ASNs for every purchase order.
2. Can one ASN cover multiple POs?
Yes, provided all POs are on the same truck and bound for the same DC or FC. If the same PO is split across multiple trailers, each trailer must have a unique ASN document ID.
3. What happens if I do not correct ASN errors?
Unresolved errors result in non-compliance and SQEP penalties. Correcting and resending before gate-in is mandatory.
4. How do I know if my ASN was successful?
Confirm via the EDI 997 acknowledgement, review 824 messages, and check the ASN Dashboard in Retail Link.
5. What happens if an ASN is rejected?
If an ASN is rejected (via 997 or 824), it must be corrected and retransmitted before the shipment arrives at the Walmart facility.
6. What if the ASN only has warnings, not errors?
Warnings indicate non-critical issues, and the ASN will still be processed. However, suppliers are encouraged to correct them because Walmart may convert warnings into errors in the future.
7. How do I access the ASN article in Retail Link?
Navigate to: Retail Link Academy Getting Started EDI Advance Ship Notice (ASN). This article contains Walmart's latest ASN requirements, mapping guides, and onboarding information.
8. How do I access the ASN Dashboard?
The ASN Dashboard can be found by navigating to: Retail Link Apps Advance Ship Notice Dashboard. Retail Link access is required. If you encounter issues accessing the dashboard or any other Retail Link application, contact the EDI Tech Support team at (479) 273-8888.