SKU
Catalog
Stock Keeping Unit. The seller's internal identifier for an inventory item. Amazon allows the seller to assign any SKU; FNSKU is generated automatically by Amazon for FBA tracking.
SKU, or Stock Keeping Unit, serves as the seller's internal identifier for inventory management, allowing for efficient tracking and organization of products. Each seller can create SKUs according to their own system, with no character limit imposed by Amazon, although best practices suggest keeping them concise for ease of use. For FBA sellers, Amazon generates a unique FNSKU, which matters for tracking inventory across fulfillment centers in EU marketplaces such as DE, FR, IT, ES, and UK. This FNSKU must be used on products sent to Amazon warehouses, ensuring proper identification during the fulfillment process. Sellers must also consider that while creating SKUs, they should avoid duplicating existing ASINs, as this can lead to listing errors and inventory discrepancies. Additionally, maintaining a clear SKU structure can enhance reporting capabilities, such as analyzing sales performance through the Inventory Performance Index (IPI) report, which evaluates inventory health and helps sellers make informed restocking decisions. The trade-off for a more complex SKU system is the potential for confusion in inventory management, especially for sellers with large catalogs. Regular audits of SKUs are recommended, ideally on a quarterly basis, to ensure alignment with inventory levels and sales data.