What Are EDI Transactions? 850, 855, 856, and 810 Explained

EDI transactions are the standardized electronic documents that retailers and vendors use to place an order, confirm it, ship it, and get paid, without a single PDF or spreadsheet passed back and forth by hand. If you're launching a product into Walmart, Target, Kroger, or any major retailer, you'll run into four of these constantly: the 850, 855, 856, and 810. Here's what each one actually does, how they connect, and where brands get tripped up.

What is EDI?

EDI stands for Electronic Data Interchange: a standardized way for two companies' computer systems to exchange business documents automatically. In the US, retail EDI runs on the ANSI X12 standard (opens in new tab), maintained by the same standards body most major retailers reference in their vendor manuals.

Each type of document, a purchase order, an invoice, a shipping notice, is called a transaction set and gets a three-digit number. Retailers publish an EDI compliance guide (often 50 to 100+ pages) spelling out exactly which fields they expect, in what format, and by when. Miss the spec, and you're not just annoying your buyer, you're often opening yourself up to a chargeback.

What is the EDI 850 (Purchase Order)?

The 850 is the retailer's order. It's the document that starts the clock on everything downstream.

A typical 850 includes:

• PO number, date, and type (regular, replenishment, or promotional)
• Ship-to location, usually a specific distribution center
• Requested delivery window, often a Must Arrive By Date (MABD)
• Line items with item numbers, quantities, and unit pricing
• Routing instructions naming the required carrier and freight terms
• Any store- or program-specific instructions

Once the 850 lands, the retailer expects a response, which is where the 855 comes in.

What is the EDI 855 (Purchase Order Acknowledgment)?

The 855 is your formal reply to the 850: you're confirming you can fulfill the order as written, or flagging where you can't.

An 855 carries the original PO reference number, an accept, reject, or modify status, and, when something has to change, the actual ship date and quantities you can commit to. Skipping this step, or sending it late, means the retailer is planning inventory and shelf space around numbers you never actually agreed to. That gap is where a lot of avoidable friction starts.

What is the EDI 856 (Advance Ship Notice)?

The 856, usually called the ASN, tells the retailer exactly what's on the truck before it arrives, down to the pallet and carton level.

A complete ASN includes the shipment ID, carrier and bill-of-lading number, and a full pack hierarchy: which items are in which carton, on which pallet, each tagged with an SSCC-18 code (a standardized GS1 shipping container identifier (opens in new tab)). When the retailer's dock scans a carton, that scan has to match the ASN exactly.

This is the transaction set that causes the most chargebacks, and the fix is almost always the same: generate the ASN from actual pick-and-pack scan data, not from what you intended to ship. One retail compliance guide puts a late or inaccurate ASN at roughly 3% of invoice value per violation, which adds up fast at volume. It's also the transaction most tied to a retailer's routing guide, since routing guides typically dictate carrier selection, appointment scheduling, and labeling right alongside ASN timing. We cover that side of compliance in Routing Guide 101: 5 Rules Every Retail Vendor Must Know.

What is the EDI 810 (Invoice)?

The 810 is your bill for the goods you shipped, sent once the ASN has gone out.

It includes the invoice number, the PO it's tied to, line items that match the ASN's quantities and pricing, any allowances or promotional discounts, and payment terms (net 30, net 60, and so on). Retailers run a three-way match between the 850, 856, and 810: if the numbers don't line up, the invoice doesn't fail outright, but payment stalls until someone resolves the mismatch. For a vendor counting on that cash, a stalled invoice is its own kind of problem.

How the four EDI transactions fit together

There's a quieter fifth document worth knowing: the 997, a functional acknowledgment that simply confirms an EDI file was received and readable. It doesn't say anything about the order itself, just that the transmission came through cleanly. Most EDI systems generate it automatically.

What happens when EDI transactions go wrong

Chargebacks. A missing 855, a late 856, or an 810 that doesn't reconcile with the PO all give the retailer grounds to deduct from your payment, on top of the operational headache of a shipment sitting unreceived at a distribution center. For a vendor doing a few million dollars a year with one retailer, the difference between tight EDI compliance and sloppy compliance can run into the tens of thousands of dollars annually.

Most brands don't build EDI capability from scratch. If you're weighing whether to handle it in-house or hand it to a provider, we compare the main options for early-stage vendors in Best EDI Providers for Startups.

FAQ: EDI transactions

Do I need all four EDI transactions to sell to a retailer? Almost always, yes. Retailers require the 850, 855, 856, and 810 as a baseline before they'll set you up as a vendor, and most spell this out explicitly in their vendor compliance guide.

What's the difference between EDI 850 and 810? The 850 is the retailer's purchase order, placed before anything ships. The 810 is your invoice, sent after the goods have shipped, billing for what went out.

Is EDI required for Amazon vendors too? Yes, for Amazon Vendor Central (1P) relationships. Amazon uses the same core transaction sets, 850, 855, 856, and 810, with its own specific formatting requirements layered on top.

How long does it take to become EDI compliant? It depends on the path. A managed EDI provider can often get a new vendor transacting in two to four weeks. Building and testing an in-house integration usually takes longer.

What is an EDI 997? It's a functional acknowledgment, a short document confirming that an EDI file was received and could be read, separate from whether the order inside it was accepted.

book a call with Izba and we'll walk through your specific retailers' requirements and where to start.