What is EDI? A Retail Vendor’s Guide to Electronic Data Interchange

What is EDI (Electronic Data Interchange)?

Electronic Data Interchange (EDI) is the computer-to-computer exchange of standard business documents between trading partners. Instead of emailing purchase orders, faxing invoices, or calling in shipping details, EDI transmits these documents electronically in a standardized format that both systems can read and process automatically.

If you’re a D2C brand that just landed your first retail deal, EDI is probably the biggest technology surprise you’ll face. When a retail buyer asks “Do you have EDI capabilities?” they’re asking whether your systems can exchange purchase orders, shipping notices, and invoices electronically—because every major retailer requires it.

In the United States, most retail EDI follows the ANSI X12 standard, maintained by the Accredited Standards Committee X12. Each document type is identified by a three-digit number—an EDI 850 is a purchase order, an EDI 856 is a shipping notice, and an EDI 810 is an invoice. Internationally, some trading partners use EDIFACT (used primarily in Europe) or proprietary XML formats, but ANSI X12 dominates US retail.

A Brief History of EDI

EDI is one of the oldest digital business technologies still in active use. Its roots trace back to the late 1960s and early 1970s, when the transportation industry began experimenting with computer-to-computer document exchange. In 1975, the Transportation Data Coordinating Committee (TDCC) published the first EDI standards for shipping and warehouse documents.

The retail industry adopted EDI in the 1980s, driven by large retailers like Walmart and Kmart who saw it as a way to reduce paperwork, speed up supply chain operations, and lower costs. In 1979, the American National Standards Institute (ANSI) chartered ASC X12 to develop a universal EDI standard that would work across industries. The X12 standard has been updated regularly ever since and remains the foundation of US retail EDI today.

By the 1990s, EDI was effectively mandatory for any company doing business with major retailers. The rise of the internet introduced new transmission methods (like AS2) but didn’t replace the underlying X12 document standards. Today, despite the availability of modern APIs, EDI remains the dominant method for B2B document exchange in retail because of the massive installed base and the cost of switching.

How EDI Replaces Manual Processes

Without EDI, a typical retail order cycle looks like this: the retailer emails or faxes a purchase order, someone on your team manually enters it into your system, you ship the product, then you create and mail or email an invoice. Every manual step introduces errors—wrong quantities, transposed item numbers, delayed invoices—that lead to chargebacks and payment delays.

With EDI, the retailer’s system sends a purchase order (EDI 850) directly to your system. Your system acknowledges it (EDI 855), generates the shipping notice when the order ships (EDI 856), and transmits the invoice (EDI 810)—all automatically, with no manual data entry. This eliminates transcription errors, speeds up the order-to-cash cycle, and is exactly what retailers mean when they say “EDI capable.”

The EDI Transaction Sets Every Retail Vendor Needs to Know

EDI documents are called transaction sets, and each one has a three-digit number. Think of them as standardized digital forms—every EDI 850 follows the same structure no matter which retailer sends it, which is what makes automated processing possible. Here are the transaction sets you’ll encounter as a retail vendor:

The Core Four: 850, 855, 856, 810

For most retail vendors, four transaction sets form the backbone of every order cycle:

The EDI 850 (Purchase Order) starts everything. The retailer sends you an electronic purchase order specifying what they want, how many units, the price, and where to ship it. Your system receives this and can automatically create a sales order in your ERP or inventory system.

The EDI 855 (Purchase Order Acknowledgment) is your response. It tells the retailer you received their order and confirms you can fulfill it—or flags any line items you can’t fill. Not all retailers require the 855, but it’s good practice to always send one.

The EDI 856 (Advance Ship Notice / ASN) is sent when you ship the order. It tells the retailer exactly what’s on the truck—which items, in which cartons, with which SSCC barcodes, arriving when. The ASN is the single most important EDI document for compliance because missing or late ASNs are the #1 source of retail chargebacks. Read our complete ASN guide →

The EDI 810 (Invoice) replaces your paper or emailed invoice. It’s sent after the shipment and must match the purchase order (850) and shipping notice (856) in quantities and prices. Mismatches between these three documents are a common source of payment delays and deductions.

Additional Transaction Sets

Beyond the core four, you may encounter the EDI 820 (Payment Order/Remittance Advice), which the retailer sends when they pay you, detailing which invoices are being paid and any deductions. The EDI 860 (Purchase Order Change) is sent by the retailer to modify an existing order—changing quantities, adding items, or adjusting ship dates. The EDI 846 (Inventory Inquiry/Advice) shares inventory availability between trading partners, and the EDI 997 (Functional Acknowledgment) is an automated receipt confirming your system received an EDI transmission.

Which Retailers Require EDI?

Nearly every major US retailer requires EDI from their vendors. The specific transaction sets, portals, and timelines vary, but the expectation is universal: if you want to sell to big retailers, you need EDI capabilities.

What Happens If You Don’t Have EDI

The consequences of not having EDI—or having a poorly implemented EDI setup—are financial and operational. Here’s what vendors face:

EDI in Practice: What a Retail Order Actually Looks Like

To understand how EDI works in the real world, let’s walk through a complete order cycle between a vendor and Target. This example shows every EDI touchpoint from purchase order to payment.

This entire cycle—from purchase order to payment—happens electronically with minimal human intervention when EDI is properly configured. The key insight for new vendors is that every step is connected: errors in the 856 ASN cascade into receiving problems, which cause 810 invoice mismatches, which delay 820 payment. Getting the data right at each step is what EDI compliance is all about.

EDI for Small Business: Your Options

The single biggest concern for small businesses entering retail is EDI cost. The good news is that you have several options, and the right choice depends on your order volume and technical infrastructure.

How to Choose the Right EDI Solution

The decision typically comes down to volume. If you’re shipping fewer than 50 orders per month to a single retailer, a web-based EDI portal is the simplest and cheapest option—you log in and manually enter transaction data through a browser interface. At 50–200 orders per month, an integrated EDI solution that connects to your ERP or inventory system eliminates manual data entry and reduces errors. Above 200 orders per month, you need full-service EDI with dedicated support.

If you’re using a third-party logistics provider (3PL), check whether they offer EDI as part of their services. Many 3PLs handle EDI on behalf of their clients at no additional cost, which can be the simplest path for small brands. Your 3PL’s warehouse management system generates the ASN, transmits the shipping notice, and handles the technical integration with each retailer’s requirements.

How to Set Up EDI: Step-by-Step

Setting up EDI typically takes 4–8 weeks from start to go-live. Here’s the process:

What to Expect During EDI Testing

EDI testing (sometimes called “certification”) is where most delays happen. The retailer sends you test purchase orders, and you respond with test acknowledgments, ASNs, and invoices. Their system validates every field—are your item numbers correct? Are the quantities in the right format? Is the SSCC structure valid? Does your invoice reference the correct PO number?

Expect to go through multiple rounds of testing. Your first submission will almost certainly have errors—a missing segment, an incorrect qualifier code, a data element in the wrong position. This is normal. Your EDI provider should handle the technical debugging, but you’ll need to provide business data: your GS1 Company Prefix, item numbers, prices, and product descriptions.

Some retailers are more rigorous than others. Costco, for example, requires formal certification through SPS Commerce before go-live. Walmart allows vendor self-testing through Retail Link. Target reviews test files and approves vendors individually. Ask your retail buyer or vendor onboarding contact what their specific testing process looks like.

Timeline tip: Start EDI setup as soon as you sign the vendor agreement—not when you receive your first purchase order. Many new vendors underestimate the setup time and end up scrambling to get EDI working before their first PO arrives.

Your GS1 Company Prefix is required for EDI because it’s the foundation for your product identification (GTINs/UPCs) and shipping container codes (SSCCs). If you don’t already have one, register at gs1us.org. Learn about GS1-128 labels and SSCC codes →

EDI Compliance: What Retailers Actually Check

Having EDI set up is only half the battle—you also need to keep your EDI transactions compliant. Retailers actively monitor EDI quality and issue chargebacks or scorecard deductions when vendors fall short.

What Gets Checked

The Three-Way Match: How Retailers Catch Errors

The three-way match is the foundation of retail EDI compliance. When your invoice (810) arrives, the retailer’s system automatically compares it against the original purchase order (850) and the shipping notice (856). All three documents must agree on quantities, item numbers, and prices.

For example, if the 850 ordered 500 units, the 856 reported 500 units shipped, but the 810 invoices for 520 units, the mismatch flags the invoice for review. The retailer will either reject the invoice entirely or pay for 500 units and deduct the remaining 20. Either way, the error creates work for your accounts receivable team and delays payment.

The most dangerous mismatches are between the 856 ASN and physical shipment. If your ASN says a carton contains 20 units of product A but it actually contains 18 units of product A and 2 units of product B, the retailer’s automated receiving system will flag the discrepancy. The result is chargebacks, manual recounts at the DC, and a hit to your vendor scorecard. This is why your ASN data must be generated from the same system that prints your shipping labels—never from a separate manual process.

EDI vs. API: The Modern Alternative

If EDI feels like legacy technology, you’re not entirely wrong. EDI has been around since the 1970s, and modern APIs (Application Programming Interfaces) offer a more flexible, real-time alternative. But in retail, EDI isn’t going anywhere soon.

Amazon Vendor Central is the most prominent example of API-based integration in retail. Instead of traditional EDI, Amazon uses its own API layer that vendors interact with through the Vendor Central web portal or programmatically via the SP-API (Selling Partner API). However, Amazon still supports traditional EDI for vendors who prefer it.

The reality for most retail vendors in 2026 is that you’ll need traditional EDI for Walmart, Target, Kroger, and most other brick-and-mortar retailers, even if you use API-based integration for Amazon. Modern EDI providers like SPS Commerce and TrueCommerce bridge this gap by offering both EDI and API connectivity through a single platform.

Some industry observers expect a gradual shift toward API-based integration over the next decade, but the installed base of EDI systems is massive. Retailers have decades of infrastructure built around EDI, and switching costs are high. For the foreseeable future, retail vendors need to be EDI capable.

Common EDI Mistakes First-Time Vendors Make

After working with hundreds of retail vendors, these are the EDI mistakes we see most often—especially from D2C brands entering retail for the first time:

How EDI Works: VANs, Standards, and Connectivity

Understanding the technical layer of EDI helps you evaluate providers and troubleshoot issues. You don’t need to become an EDI expert, but knowing these concepts will make conversations with your EDI provider and retail partners more productive.

Value Added Networks (VANs)

A VAN (Value Added Network) is a private network that acts as a secure middleman between trading partners. Think of it like a postal service for EDI documents—your system sends the document to the VAN, and the VAN routes it to the retailer’s system. VANs handle encryption, delivery confirmation, and format translation between different systems.

Major VANs include SPS Commerce, OpenText (formerly GXS), IBM Sterling, and TrueCommerce. Most EDI providers include VAN connectivity as part of their service—you don’t typically need to set up a separate VAN relationship.

EDI Standards

The most common EDI standards are:

• ANSI X12: The dominant standard in North American retail. Maintained by ASC X12. All the three-digit transaction set numbers (850, 856, 810) come from this standard.
• EDIFACT: The UN/EDIFACT standard used primarily in Europe and international trade. The EDIFACT equivalent of an ASN is called a DESADV.
• GS1 EANCOM: A subset of EDIFACT used by GS1 for supply chain messages, common in European grocery and retail.

Connection Methods

EDI documents can be transmitted via several methods:

• VAN-to-VAN: The traditional method. Both trading partners connect to their respective VANs, which handle routing. Reliable but adds per-transaction costs.
• AS2 (Applicability Statement 2): A direct, point-to-point connection using HTTPS. Walmart popularized AS2 and requires it for direct EDI connections. Eliminates VAN fees but requires more technical setup.
• SFTP: Secure file transfer protocol. Simple to implement, used by some smaller trading partners. Less common for major retailers.
• Web EDI: Browser-based interface where you manually enter transaction data. No technical integration required, but doesn’t scale.

EDI Glossary

Quick reference for the most common EDI terminology you’ll encounter:

Frequently Asked Questions About EDI

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