Costco EDI Requirements And Common Documents (PO, ASN, Invoice)

The electronic exchange of standardized business documents between Costco and a supplier, including purchase orders, acknowledgments, ASNs, invoices, inventory data, and related transactions.

Costco EDI The electronic exchange of standardized business documents between Costco and a supplier, including purchase orders, acknowledgments, ASNs, invoices, inventory data, and related transactions.

This article lists the essential EDI requirements and the specific documents you’ll exchange with Costco. For suppliers to ship into Costco distribution centers or club stores reliably, they must satisfy both message-level rules (which EDI transaction sets to use) and physical-labeling and packing requirements that receiving teams use to confirm shipments. Failing to meet Costco’s expectations typically results in receiving delays or financial penalties.

Key Transaction Sets And Their Purpose

Cosco uses standard EDI X12 transaction sets. At minimum, suppliers should implement the following and understand their business role.

• 850 (Purchase Order): Sent by Costco to request goods. Contains quantities, requested delivery dates, and ship-to location codes.
• 855 (PO Acknowledgment): Supplier responds to accept or decline each PO line and signal ship date feasibility.
• 856 (Advance Ship Notice / ASN): Details packing structure — pallet SSCCs, carton counts, UPCs/GTINs, and carrier/trailer info.
• 810 (Invoice): Electronic billing document used for payment; must reference the PO and shipment identifiers.
• 846 (Inventory Inquiry/Advice): Used in certain replenishment or vendor-managed inventory cases to share current stock levels.

Labeling And Packing Requirements

Costco and its DCs operate high-throughput receiving lanes that depend on consistent labels and pallet construction. Key expectations include carton and pallet labels with readable GTIN/UPC, case pack quantities, and SSCCs printed as human-readable text and barcode. Pallets should conform to Costco’s dimension and weight limits, and cartonization must match what’s declared in the ASN.

Timing And ASN Rules

ASN timing is important. Costco typically expects ASNs to arrive prior to or at the time of shipment departure so the DC can pre-plan receiving. The ASN must match the physical shipment: number of cartons, pallet SSCCs, and carrier information. Discrepancies — for example, an ASN showing 10 cartons while the truck carries 12 — create receiving exceptions and may delay putaway.

Data Elements That Often Trigger Exceptions

Certain fields in EDI transactions are frequently validated by Costco’s systems and by DC receiving teams. Make sure these are accurate to avoid manual interventions.

• GTIN/UPC Accuracy: Wrong or missing UPCs break PO-line matching and can lead to refused receipts.
• SSCCs: Pallet serial numbers must be unique, consistent between ASN and labels, and GS1-compliant.
• Case Pack Counts: ASN carton quantities must reflect actual packing and the PO’s case pack rules.
• Carrier & Trailer Info: Accurate pro numbers and carrier codes help schedule appointments and match deliveries.

Chargebacks And Penalties

Costco enforces receiving rules through chargebacks for non-compliance — for late ASNs, incorrect labeling, inconsistent case counts, missed appointments, or other violations. Chargeback policies vary by program and vendor category, so suppliers must review their Costco vendor agreements and billing terms. Preventing chargebacks is primarily a function of accurate EDI data and consistent physical processes at the pack and ship stages.

Testing, Onboarding, And Ongoing Governance

Onboarding includes technical connectivity tests (AS2, VAN, SFTP), message syntax validation, and business-content validation using sample transactions. Costco will typically require test POs and mock ASNs to verify mapping and label generation. After go-live, maintain governance through periodic reconciliation reports, exception trending, and scheduled re-tests when significant system changes occur.

Integration Tips For Suppliers

Well-integrated suppliers minimize manual interventions and chargebacks. Follow these practical steps:

• Centralize Mappings: Use an EDI translation layer so updates to Costco’s spec don’t force ERP changes.
• Automate Label Printing: Tie SSCC generation to your WMS and print labels at pack time.
• Reconcile Daily: Match Costco POs to ASNs and invoices each day to catch mismatches early.
• Document Processes: Keep a vendor checklist for PO acknowledgment SLAs, ASN windows, and label templates.

Practical Example

A supplier receives a Costco PO for 600 cases split across two cartons per case pack. They must send an 855 within the agreed SLA if dates differ, create an ASN listing three pallets with SSCCs and carton detail, print GS1-compliant labels for each carton and pallet, and submit an 810 invoice referencing the PO and SSCCs after delivery. Any mismatch can prompt a chargeback or delay payment.

In short, the Costco EDI program relies on a small set of critical transactions plus strict labeling, packing, and timing rules. Suppliers who standardize their ASN and labeling processes, validate GTINs, and maintain disciplined testing and reconciliation reduce exceptions and operate more smoothly within Costco’s high-volume supply chain.