How CastleGate Fulfillment Works: Onboarding, Inventory Flows, And Shipping For U.S. Suppliers

Wayfair’s warehousing and fulfillment service for storing supplier inventory and shipping customer orders.

CastleGate Fulfillment is Wayfair’s warehousing and fulfillment service for storing supplier inventory and shipping customer orders. Understanding the operational flow—from onboarding and inbound requirements to picking and carrier handoff—helps suppliers reduce delays and avoid unexpected fees.

The CastleGate operational model aligns supplier activity with Wayfair’s marketplace expectations. Below is a practical walkthrough of the typical steps and the supplier responsibilities at each stage for U.S. operations.

Onboarding And Account Setup

Onboarding begins with contractual enrollment and data integration. Suppliers receive Wayfair’s inbound routing instructions, packaging and labeling requirements, and a list of CastleGate receiving sites. Integration usually involves mapping SKUs in Wayfair’s merchant portal and setting up EDI/API feeds for ASN (advance ship notice) and inventory updates.

Inbound Shipments: Preparing For Receiving

• Pallet and packaging standards: Follow Wayfair’s pallet configurations, stretch-wrap rules, and protective packaging guidelines to minimize damage and receiving rejections.
• Labeling: Apply Wayfair-specified carton and pallet labels with scannable barcodes and SKU/PO details to speed receiving and reduce chargebacks.
• ASN and documentation: Send accurate ASNs through Wayfair’s systems before carrier pickups to align expected vs. received quantities.

Receiving, Putaway, And Inventory Management

CastleGate receiving teams inspect shipments for obvious damage, verify pallet counts and carton markings, and scan items into Wayfair’s inventory system. Proper SKU matching and accurate counts prevent stock discrepancies that can impact storefront availability. Some suppliers use pre-inspection at origin to reduce receiving disputes.

Order Picking, Packing, And Shipment

Once integrated, Wayfair routes customer orders to CastleGate where pickers retrieve items, pack per item-specific packing rules (for dimensional weight and damage protection), and print Wayfair carrier labels. CastleGate leverages Wayfair’s negotiated carrier contracts and LTL/parcel routing rules to optimize cost and delivery speed for bulky home goods.

Carrier Handoffs And Tracking

• Carrier selection: Wayfair’s routing logic selects the appropriate carrier and service level for each order.
• Tracking integration: CastleGate systems push tracking numbers back into Wayfair’s order system so customers and the supplier can see delivery progress.
• Claims and damage handling: CastleGate typically manages initial damage claims; suppliers should track root causes and adjust packaging or palletization accordingly.

Returns And Reverse Logistics

Returns flow back to CastleGate or designated returns facilities. Wayfair’s disposition rules determine whether a returned item is restocked, refurbished, or returned to the supplier. Suppliers should confirm the financial treatment for returns to estimate net sold inventory correctly.

Metrics And Performance Expectations

Wayfair tracks metrics important to CastleGate operations: inventory accuracy, on-time shipping, damage rates, and returns disposition speed. Suppliers must hit predefined thresholds to avoid penalties or operational restrictions. Regularly reviewing these KPIs in Wayfair’s merchant portal allows corrective action before penalties apply.

Practical Checklist Before Sending Your First Pallet

• Confirm SKU mapping: Ensure SKUs in your ERP match Wayfair SKU IDs to prevent mispicks.
• Verify pallet specs: Confirm pallet dimensions, weight limits, and stacking instructions.
• Test ASN accuracy: Send a pilot ASN and confirm it reconciles on receipt.
• Label samples: Provide label samples and get receiving sign-off to avoid exceptions.

In short, the CastleGate Fulfillment workflow centralizes Wayfair-destined inventory inside Wayfair-controlled warehouses, reducing per-order friction and leveraging Wayfair’s carrier network. Success requires precise onboarding, strict compliance with inbound packaging and labeling rules, and ongoing monitoring of fulfillment KPIs to control costs and maintain marketplace performance.