What is an ASN? Understanding Walmart's Updated Validation Process

7 min read

Learn about:

  • ASN validation at Walmart

  • Walmart's new ASN business rules

  • ASN best practices

An Advance Shipping Notice (ASN), also known as EDI 856, is a document used to transmit information about a shipment to a customer before its delivery. For Walmart suppliers, ASN expectations are changing as Walmart updates its ASN business rules.

ASN Validation at Walmart

Walmart's ASN validation process involves three EDI documents:

  • EDI 856 (Advance Shipment Notice)

  • EDI 997 (Functional Acknowledgment)

  • EDI 824 (Application Advice)

The unique progression of each ASN is contingent upon the success of each step in the validation process. When a supplier sends an ASN (EDI 856) to Walmart, they will receive a Functional Acknowledgment (EDI 997) in return. This document informs the supplier of one of two things:

  1. The acknowledgment was successful, and Walmart accepted the data

  2. The document was rejected, and Walmart's system is unable to read the data

If the supplier receives a 997 rejection, they must correct the document and resend it. If the supplier receives no 997, this could indicate an issue that prevented the ASN from being processed or that the ASN was never sent. If this happens, Walmart recommends that the supplier review their EDI Sender/Receiver IDs or contact their EDI support team for help.

Once a successful 997 is received, the supplier should still monitor for an Application Advice (EDI 824) transmission. An EDI 824, sent with the text ERROR or WARN, indicates an issue with the ASN that needs to be addressed, such as a missing or invalid UPC, invalid GLN, etc. It's important to address both errors and warnings, but errors are more urgent.

An EDI 824 received without the error/warning text means Walmart considers the ASN as a complete ERROR, meaning that the document was fully rejected. Walmart defines WARN/ERROR as the following:

  • Warn = The data in the ASN failed a business rule, but the failure is not critical. This means Walmart can still utilize the ASN data. Correcting warnings and resending the ASN is best practice and strongly recommended by Walmart. 

  • Error = The ASN data was fully rejected and cannot be utilized by Walmart. Errors should be corrected immediately and resent (before the shipment arrives at a Walmart distribution center).

This graph from Walmart depicts the journey of an ASN:

The flowchart titled "ASN Process" outlines the steps for handling Advanced Shipping Notices (ASNs) for all Purchase Orders (POs). The process begins with the supplier sending the ASN for all purchase orders. The supplier then checks for a Functional Acknowledgement (997 FA). If the 997 FA is acknowledged, the process continues to the next step. If the 997 FA is rejected, the supplier makes corrections to the ASN based on the FA and resends it. Once the 997 FA is acknowledged, the supplier checks for any 824 error messages. If an 824 error message is received, the supplier makes corrections to the ASN and resends it. If no error messages are received, the ASN is loaded into the Distribution Center (DC) system without errors, completing the process. Source: Retail Link > Academy > Quick Learning Articles > 4. Transportation Channels > Flow Methods > Advance Ship Notice (ASN)

Related Reading: EDI for Retail Supply Chains Cheat Sheet

Walmart's New ASN Business Rules

As of May 2024, Walmart has implemented more stringent ASN standards to align its business rules with its EDI mapping guides. Walmart states these changes will allow "more of the ASN data to be used and aid with automation and freight tracking."

These changes will result in more data on ASNs being scrutinized for correctness and an increase in 824 transmissions with error and warning messages. However, Walmart states that the new error and warning 824 transmissions (also appearing in the ASN dashboard in Retail Link) will not result in new SQEP charges. It should be noted that it has been Walmart's process to implement a standard, then begin tracking compliance, and eventually levy fines/charges.

The diagram titled "Exception Type" highlights the distribution of ASN exceptions and the handling of current and future 824 error messages. For current 824 error messages, all errors are charged. Future 824 error messages will follow the same charging process as current 824 errors, but new error messages will not result in SQEP charges.

Source: Retail Link > Academy > Quick Learning Articles > 4. Transportation Channels > Flow Methods > Advance Ship Notice (ASN)

ASN Dashboard in Retail Link

With these new expectations, Walmart is increasing visibility into the causes behind 824 transmissions within the Advance Shipment Notice Dashboard in Retail Link.

Within the Advance Shipment Notice Dashboard, the IDOCS tab on the left-hand side provides insight into ASN compliance. On this page, you can use the Coverage chart to see what percentage of your POs were shipped with/without an ASN. Toggling to Exception Distribution on the same chart allows you to see what percentage of ASNs resulted in an error or warning notification from Walmart.

Source: Retail Link > Academy > Quick Learning Articles > 4. Transportation Channels > Flow Methods > Advance Ship Notice (ASN) > ASN Dashboard Video

The Exception Distribution chart shows 824 transmissions separated by type of error or warning (e.g., Invalid PO Number, Invalid Shipment Date, etc.). This will allow you to pinpoint particular pain points in your ASN process or identify recurring errors.

Walmart has an ASN 824 Resolution Guide (also called IDOCs Error - Quick Reference Guide) to help suppliers quickly identify and decipher error and warning messages they receive on ASN 824 transmissions.

There are several ways you can access the ASN 824 Resolution Guide in Retail Link:

  • Retail Link > Apps > EDI-B2B > EDI 824 Application Advice--ASN Rejections

  • Retail Link > Apps > Advanced Shipment Notice Dashboard > Information button in top right-hand corner > Helpful Information > 824 Resolution Guide

  • Retail Link > Apps > Advanced Shipment Notice Dashboard > IDOCS > Exception Distribution > Help button 

ASN Best Practices

Understanding Walmart's ASN expectations and best practices can help you avoid ASN errors and warnings in the first place. Walmart expects all ASNs to arrive on time and error-free. To make that expectation a reality, Walmart outlines three areas suppliers should focus on. Every ASN sent to Walmart should be:

Timely — ASNs must arrive on time. Walmart considers an ASN to be on time if the transmission:

  • Arrives before the gate-in time of the shipment/trailer at a Walmart facility 

  • Passes all validation rules (or all issues have been corrected and resent before gate-in)

Accurate — Walmart holds suppliers accountable for the accuracy of ASNs. The supplier should ensure that each ASN has the following: 

  • Lines on the PO match the ASN

  • Items included on the ASN align with the physical shipment

  • Quantity on the ASN matches the physical shipment that arrives at the distribution center

Complete — Walmart considers an ASN to be complete if: 

  • The ASN includes all content outlined in the Walmart mapping guides

  • The data provided is complete and correct

Related Reading: SQEP Handbook

Stay Informed with SupplierWiki

As a supplier, staying up-to-date with the latest processes, guidelines, and best practices is crucial for maintaining compliance with Walmart. SupplierWiki is your go-to resource for all the information you need to navigate Walmart's requirements and stay informed about industry updates.

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Written by The SupplyPike Team

About The SupplyPike Team

SupplyPike builds software to help retail suppliers fight deductions, meet compliance standards, and dig down to root cause issues in their supply chain.

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The SupplyPike Team



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