Amazon allows sellers to identify products using either a manufacturer barcode (such as a UPC or EAN) or an Amazon-generated FNSKU. Choosing the correct option is important for inventory accuracy and fulfillment.
🏷️ What Is an FNSKU?
An FNSKU (Fulfillment Network Stock Keeping Unit) is a unique barcode assigned by Amazon to identify inventory belonging to a specific seller.
Unlike manufacturer barcodes, each seller receives a unique FNSKU for their inventory.
📦 When Should You Use an FNSKU?
Prevent Inventory Commingling
Using an FNSKU ensures that Amazon tracks your inventory separately from inventory sold by other sellers offering the same ASIN.
Sell Used or Collectible Items
Many used, collectible, or condition-sensitive products should be labeled with an FNSKU to ensure the correct inventory is shipped to customers.
Maintain Seller-Specific Inventory Tracking
An FNSKU allows Amazon to identify exactly which seller owns each unit in the fulfillment center.
Avoid Receiving Issues
Some products or categories may require FNSKU labeling based on Amazon's fulfillment requirements.
🏷️ When Can Manufacturer Barcodes Be Used?
Manufacturer barcodes may be suitable when:
Products are new
Inventory is eligible for barcode commingling
Seller prefers Amazon to use manufacturer identifiers
Not all products are eligible for manufacturer barcode tracking.
✅ Summary
FNSKUs are typically recommended when sellers want inventory tracked separately, are selling used items, or want greater control over fulfillment accuracy.