Costco EDI Requirements: The Complete 2026 Vendor Guide

Costco Wholesale operates the world's largest membership warehouse club, and getting onto their shelves is a major milestone for any consumer brand. But Costco's supply chain is built around massive pallet-level flow, cross-docks, and tight depot appointments — and their EDI requirements reflect that scale. Miss a shipping window or send a bad ASN and you won't just get a chargeback, you'll get a call from your buyer.

Costco vendors ship either direct-to-warehouse (DTW), depot (DC), or drop-ship for Costco.com. Each flow has its own EDI nuances, but all of them require clean, on-time documents.

Required EDI Documents

Costco places heavy emphasis on the 856. Their depot receiving teams scan SSCC labels to flow pallets directly to outbound trucks, so label and hierarchy mistakes cause real operational problems.

Vendor Requirements

Costco's vendor scorecard focuses on four things:

• Ship window compliance: you must ship within the stated MABD window
• ASN accuracy: pallet count, carton count, and SSCC data must match reality
• Label compliance: GS1-128 pallet labels with the correct AI segments
• Invoice match: the 810 must tie exactly to the 856 and the PO

Costco buyers are direct, and your relationship with them depends as much on operational reliability as it does on product.

Chargebacks and Risk

Costco chargebacks are less frequent than Walmart's but tend to be larger per incident because the shipment sizes are larger. Key risk areas:

• Late delivery to depot: freight deduction plus service fees
• Pallet rebuilds: if labels or hierarchy are wrong, Costco's depot rebuilds the pallet and bills you
• Short shipments: units short on a PO get deducted at cost
• Missing ASN: shipments arriving without a prior 856 can be refused

The biggest hidden cost isn't the chargeback fee itself — it's the appointment delay when a depot rejects a load, which cascades into missed in-store dates.

Where Brands Struggle

Costco uses MABD (Must Arrive By Date) rather than a simple ship date, and many vendors ship "on time" only to miss the MABD because they forgot to back into transit. Brands also struggle with pallet-level SSCC labeling because Costco requires a different hierarchy than big-box retailers like Target or Walmart. Finally, Costco.com drop-ship orders use a slightly different document flow that brands often map incorrectly.

Setup Process

1. Complete Costco's vendor onboarding and receive your vendor number
2. Request EDI credentials from Costco's EDI team
3. Receive the Costco EDI specification documents
4. Configure AS2 or VAN connectivity
5. Map 850, 855, 856, 810 and test each transaction
6. Print and validate GS1-128 pallet labels in a test shipment
7. Pass Costco's EDI certification and go live

Platform Compatibility

JayChris EDI integrates with Shopify, WooCommerce, BigCommerce, and custom ERP systems. Costco POs drop into your order workflow as normal orders, and ASNs generate from your pick-pack data automatically.

Cost Comparison

Legacy providers often quote $300 to $600 per month just for the Costco trading partner relationship, plus per-document fees and setup charges for pallet label printing.

With JayChris EDI it's $99/month + $0.25 per EDI document — all 28 retailers included, no per-retailer fees.