How to Connect via EDI with a Retailer: A Step-by-Step Overview

Step 1: The retailer's onboarding request

The process usually starts when a retailer's supplier or vendor management team sends an EDI onboarding request, either because a new supplier agreement was signed or because an existing paper-based supplier is being migrated to electronic exchange. This request typically specifies which document types are required — most commonly purchase orders (ORDERS), invoices (INVOIC) and sometimes dispatch advices (DESADV) — along with the expected transport protocol and a deadline, often 30 to 60 days out.

It is worth reading this document carefully rather than forwarding it straight to IT, because it usually also lists required master data such as GLN location codes, product identifiers and pricing conditions that need to be agreed before any technical testing can start. Missing this step is one of the most common causes of onboarding delays, since technical connectivity can be ready while commercial data is still being finalized between buyer and supplier.

Step 2: Choosing Web EDI or ERP integration

Once requirements are clear, the supplier decides how to receive and respond to the documents. A Web EDI portal is the fastest route: no development work is required, and staff log in to view incoming orders, confirm quantities, and generate matching invoices and dispatch advices directly from the interface. This is a practical choice when volumes are moderate or when a deadline is tight.

If order volumes are high or the supplier already runs an ERP such as SAP, Dynamics 365, NetSuite, WinMentor, Charisma, Senior, Clarvision or Odoo, integrating EDI directly into that system avoids double data entry entirely: orders flow in as sales orders, and invoices generate automatically from the same records used for accounting. This route takes a little longer to configure because product and pricing master data must be mapped between the ERP and the EDI messages, but it removes manual steps permanently rather than just moving them into a browser.

Step 3: Connectivity and message testing

With the method chosen, the technical connection is established using whichever protocol the retailer requires — AS2, OFTP2, SFTP, Peppol, or a VAN — and the connectivity platform maps its internal data model to the retailer's exact EANCOM or ANSI X12 specification. Every retailer's specification differs slightly even when using the same base standard, in areas like which fields are mandatory, how discounts are represented, or what qualifies as a valid delivery location, so this mapping step needs care rather than being treated as a generic one-off configuration.

Testing then follows a defined cycle: the retailer sends sample test orders, the supplier's system (or the Web EDI portal) processes them and returns the corresponding invoice or dispatch advice, and the retailer's team checks the response against their validation rules. Most retailers require a handful of clean test transactions across each document type before certifying the connection for live traffic, and it is normal to go through two or three rounds of corrections on field mapping before everything validates without errors.

• Retailer sends test purchase orders
• Supplier returns test invoices and/or dispatch advices
• Retailer validates format, pricing and required fields
• Corrections applied and retested until clean

Step 4: Go-live and monitoring

Once test transactions pass validation, the retailer switches the connection to production and live orders start arriving through the same channel used in testing. It is good practice to keep an eye on the first few weeks of live orders closely, since real order patterns — larger quantities, promotional pricing, unusual delivery addresses — sometimes surface edge cases that did not appear in the limited test set.

A connectivity platform with dashboards showing message status, delivery confirmations and error alerts makes this monitoring period far less stressful, because issues surface immediately as a flagged message rather than as a phone call from the retailer days later asking why an order was never fulfilled.

Common causes of delay

Onboarding delays rarely come from the EDI technology itself. They usually stem from incomplete master data, such as missing GLN codes or unconfirmed pricing, from internal approval processes on the supplier side taking longer than expected, or from a mismatch between what the retailer's specification document says and what their system actually validates in practice, which sometimes only becomes clear during testing.

Suppliers that assign a single internal owner for the onboarding project, rather than splitting responsibility across sales, IT and finance without clear coordination, consistently move through this process faster, since most of the delay is coordination overhead rather than technical complexity.

Working with a connectivity partner

Because retailer specifications, protocols and testing expectations vary so much, most suppliers find it faster to work with a provider that already has existing, certified connections to the major Romanian retailers — Kaufland, Carrefour, Lidl, Auchan, Mega Image, Metro, Selgros, Penny, Profi, Cora, Dedeman, Leroy Merlin, Brico Depot, Hornbach, eMAG and others — rather than negotiating a new mapping specification from scratch for every partner. This is the main reason a first connection can go live in under seven business days on an established platform, compared to weeks or months for a from-scratch build.

FAQ

What information does a retailer usually require before EDI testing starts?

Typically GLN location codes, product identifiers, agreed pricing and delivery terms, alongside confirmation of which document types (orders, invoices, dispatch advices) will be exchanged.

How many test transactions are usually required before go-live?

It varies by retailer, but most require a small set of clean test transactions across each required document type before certifying the connection for production.

Can a supplier switch from Web EDI to ERP integration later?

Yes, on a platform that supports both models, a supplier can move a retailer connection from Web EDI to direct ERP integration without renegotiating the connection with the retailer.

What transport protocols are commonly required by retailers?

AS2, OFTP2, SFTP and VAN connections are the most common, with the required protocol specified by the retailer during onboarding.