How to Set Up EDI with Walmart (Step by Step)

Setting up EDI with Walmart splits into two workstreams: the paperwork Walmart controls, and the technical build you control. The second one is this guide. With certified maps, the technical side of a Walmart connection takes 2–3 days; here is what fills them, step by step. (What Walmart requires and why is covered separately in the Walmart EDI requirements guide — this post is about getting it running.)

Step 1: Clear supplier onboarding and gather identifiers

Before any document flows you need three things from the Walmart side: a supplier agreement, your internal vendor number — the REF*IA value that must round-trip on every document you send back — and Retail Link access. On your side, every item needs an assigned GTIN and a mapped Walmart item number. Collect these first; every later step consumes them.

Step 2: Connect the platform to your ERP

Walmart trades X12 005010 over AS2 direct, so there is no VAN to contract — EDISQ holds the AS2 certificates and endpoint. Point the connector at your business system (NetSuite, QuickBooks Online, Dynamics, or any of 30+ systems) so inbound orders land as sales orders and outbound documents generate from your own shipping and billing records instead of being re-keyed.

Step 3: Load the cross-references

This is the step that decides whether go-live is quiet or noisy. Build the item table (GTIN ↔ Walmart item number ↔ your SKU), the ship-to table for DCs, and confirm the vendor number is stamped into the map. Walmart orders also pack multi-store quantities into SDQ segments, so verify your ERP explodes an SDQ line into store-level allocations rather than treating it as one shipment.

Step 4: Run Walmart's scenarios in the sandbox

Test with the failures that actually happen, not happy-path samples. Replay an 850 with SDQ distribution and check the allocations. Generate an 856 and inspect the hierarchy — Walmart rejects order-level-only ASNs, and every carton needs a GS1-128 / SSCC-18 serial in its MAN segment that matches the physical label. Then produce the 810 from the shipment data and confirm it matches PO and ASN, with allowances itemized as SAC segments.

Step 5: Certify, then go live with monitoring

Walmart certifies each document type through a short testing cycle; with pre-validated maps it is normally a single pass. Go-live is not the finish line, though — wire up two monitors before the first production order. First, 997 tracking in both directions, so a document Walmart never received gets retransmitted in minutes instead of discovered at month-end. Second, ASN timing tied to your warehouse ship-confirm event, because Walmart's OTIF program treats a late 856 as a miss even when the truck is punctual.

The snags worth knowing in advance

Three mistakes account for most rocky Walmart go-lives. Treating an SDQ line as a single shipment to one address — the explosion into store-level allocations has to happen before the warehouse picks. Dropping the REF*IA vendor number somewhere between the order and the invoice — it must round-trip on every document, and maps that rebuild documents from scratch instead of inheriting fields are where it disappears. And testing with placeholder item numbers instead of the real GTIN cross-reference, which makes the sandbox pass and the first production order fail. All three are checkable before certification; check them.

What the running system costs

Once live, you pay per document against the Production plan's $100/month minimum — applied in full to usage, Walmart included as your first live partner: the first 25 documents in a month are free, and beyond that the ladder starts at $0.50 and steps down to $0.10 as monthly volume climbs, billed marginally the way tax brackets work. The AS2 pipe, the certified Walmart maps, and the sandbox all come with it — no setup invoice, no mapping fees. The full ladder is on the pricing page, and if Sam's Club is next on your list, the directory shows how the two setups share one item cross-reference.

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