What is an EDI 856?
The 856 — usually called the ASN (Advance Ship Notice) — is the electronic packing list a supplier must send a retailer before the truck arrives. It tells the retailer's warehouse exactly what's coming and how it's packed, down to the barcode on each carton.
Why retailers require it
Receiving a truck by opening boxes and counting is slow. Receiving it by scanning carton barcodes that were announced in advance takes minutes: scan the SSCC, the system already knows what's inside because your ASN said so. That's why retailers enforce ASN accuracy with chargebacks — a wrong ASN literally breaks their receiving line.
What's inside one
A hierarchy, flattened into segments: Shipment → Order (which PO) → Pack (pallet/carton, each with its SSCC-18 barcode) → Item (UPC + quantity). Full structural walkthrough with examples: the 856 ASN guide.
856 vs the other documents
| Doc | Business name | Answers |
|---|---|---|
| 850 | Purchase order | "What do you want?" |
| 855 | PO acknowledgment | "Can you ship it?" |
| 856 | Advance Ship Notice | "What's on the truck?" |
| 810 | Invoice | "Pay me for what shipped" |
Who has to send them
Essentially every supplier to a major retailer (Walmart, Target, Kroger, Home Depot…) — the requirement lands in your onboarding packet. Big suppliers automate it through EDI providers; small suppliers mostly hand-key them into retailer portals, which is where the errors come from. The in-between —generating ASNs from a spreadsheet — is what FluentEDI builds.