Shipping to Costco: case-packs, pallets, EDI, and carriers

How Costco buys

Costco runs a 1P wholesale model. Costco’s buyers select a small assortment per category (the typical warehouse stocks under 4,000 SKUs vs 100,000-plus at a big-box retailer), negotiate a price-per-case, and write POs that you fulfill into Costco depots or, in some cases, directly to individual warehouse clubs^[1].

The buyer model means assortment turnover is intentional. Costco rotates SKUs in and out aggressively to give members a sense of treasure-hunt discovery. A SKU performing at industry-standard rates may still get cut if the buyer wants the slot for a new launch. Vendor success at Costco depends on hitting velocity targets that are higher per SKU than at any other retailer.

Becoming a Costco supplier

Costco’s supplier process is gated by buyer interest. There is no apply-online path. Brands typically engage a Costco-experienced broker, attend an industry-specific roadshow, or get a meeting through Costco’s regional buying offices. Once a buyer commits, Costco runs a New Vendor Setup process via the Costco Supplier Portal: signed Costco Vendor Agreement, proof of insurance (general liability typically $5M with Costco named as additional insured), product safety and quality certifications, and EDI capability through a supported VAN^[2].

Costco’s vendor agreement carries provisions that sometimes surprise new suppliers: cooperative funding (advertising, MVM in-club coupon programs), expectations on price competitiveness vs Kirkland equivalents, and quality sampling that runs through Costco’s independent labs.

Club-store case-pack design

Club-store case-packs are large by design. The case is the merchandising unit on the floor: an open case sitting on a pallet, slip-sheet on top so members can pull from the case. The case has to look like a display when the shipper top is removed, with unit faces oriented forward and pack count visible.

The case design is collaborative with the buyer. Brands new to Costco usually redesign packaging meaningfully for the club channel: bigger sizes, more units per ring, sturdier shippers, and merchandising-friendly outer cartons that double as display.

Costco palletization standards

Costco is a pallet-first operation. Most SKUs ship on full pallets, the pallet arrives at the depot, the depot cross-docks or short-stages the pallet, and the same pallet may end up on the warehouse floor with a Costco overlay sign on top. That means the pallet is not just a shipping unit; it is the merchandising unit.

Costco routing and the carrier list

Costco uses a small approved carrier list for inbound freight, varying by lane and mode. Vendors do not have free carrier choice for Costco-routed loads. For prepaid (vendor-routed) freight, the carrier must come from the approved list. For collect freight, Costco assigns the carrier and the pickup window. Deviating without prior authorization is one of the most common chargeback drivers^[3].

1. 1
   Receive PO via EDI 850
   PO specifies destination depot, ship-by and cancel-by dates, and routing terms (prepaid vs collect).
2. 2
   Build to case-pack and pallet spec
   Single SKU per pallet, GMA Grade A, column stacked. Confirm pack quantity matches the item file.
3. 3
   Apply pallet labels
   GS1-128 with SSCC-18, at the height specified in the Vendor Manual. Ensure the SSCC ties back to the EDI 856 ASN hierarchy.
4. 4
   Book carrier from approved list (or accept Costco-assigned)
   Confirm appointment at depot. Most depots use scheduled inbound windows.
5. 5
   Send EDI 856 ASN
   At pickup, with HL hierarchy that maps pallet to case to item.
6. 6
   BOL and POD
   Costco-formatted BOL, signed POD retained for any future dispute.
7. 7
   Invoice via EDI 810
   Net terms negotiated per category. Cooperative funding and MVM deductions appear in remittance.

EDI requirements

Costco requires EDI 850 (PO), 856 (ASN), and 810 (invoice) for active vendors. Some categories also use 855 PO acknowledgment, 753/754 routing pair for collect freight, and 846 for inventory updates. Costco supports multiple VANs and direct integrations through its supplier portal^[4].

Kirkland Signature dynamics

Kirkland Signature is Costco’s private label and represents roughly a quarter of Costco’s total sales. Many Kirkland SKUs are produced by the same brands that sell their own labeled SKUs at Costco; the Kirkland version sits next to the branded version on the floor at a lower price. If you sell into Costco in a category where Kirkland exists, expect three things over time^[5].

• Margin pressure. Buyers benchmark your case price against the Kirkland equivalent and use that anchor in negotiation.
• Co-manufacturing conversation. If the buyer rates your product quality high, they may invite you to co-manufacture the Kirkland version. The conversation is real revenue but usually carries strict packaging and IP terms.
• Assortment risk. If Kirkland enters a sub-category and Costco rationalizes, branded SKUs in that segment can get cut. Track the Kirkland pipeline through your buyer.

Quality assurance and product safety

Costco runs an aggressive QA program. Independent third-party inspections, lab testing, and audits of supplier facilities are routine. For grocery and HBA, the program references SQF (Safe Quality Food) and FSSC 22000 certifications. Failing an audit or a recall test can pull a SKU off the floor across the entire region in days^[6].

For non-grocery, Costco’s QA team focuses on labeling claims, country of origin documentation, and CPSC compliance for any product with safety implications (toys, juvenile products, lithium battery devices). Bring a complete product dossier to the first conversation, not the third.

Common chargebacks and refusals

Costco’s chargeback structure is documented in the Vendor Manual. Compared to Walmart, the absolute fines are smaller per occurrence, but refusals are more consequential because they involve full pallets sitting at a depot.

Disputes are filed through the Supplier Portal with documentation: signed BOL, depot POD, photographs of pallet at outbound, and ASN receipt confirmations. Recovery rates depend on the dispute type and the documentation quality.

Three patterns for clean Costco ops

Suppliers who scale at Costco share a few habits:

• Pallet QA at outbound is non-negotiable. Photograph every outbound pallet with the BOL visible. The pallet face is the merchandising face; photographs catch lean, off-square build, and damaged corners before they become refusals.
• Carrier discipline. Standardize on a small set of approved carriers per lane. Pre-built BOL templates per carrier reduce data-entry errors that drive late-ASN chargebacks.
• Run a Costco-specific sales rhythm. Weekly buyer touchpoints during launch quarters, monthly thereafter. Buyers manage assortment based on velocity and on personal trust with the vendor; both compound over time.

What changed in 2025 to 2026

Costco continued its international expansion in 2024 and 2025, opening warehouses in additional markets and tightening its international supplier compliance to match US standards. On ecommerce, costco.com remained a small share of total sales but grew double-digit, and Costco Logistics (CLI) expanded large-and-bulky home delivery for furniture, appliances, and exercise equipment. Suppliers in those categories now route through CLI hubs with their own labeling and BOL spec^[7].

On grocery, Costco’s sustainability and packaging guidance has tightened on single-use plastic, expanding the categories where vendors are expected to ship in recyclable substrates. The rollout has been guided more by buyer pressure than by a single published mandate, and the cleanest signal is the conversation with your category buyer.

Pre-flight compliance checklist