SKU (Stock Keeping Unit)

A SKU (Stock Keeping Unit, pronounced "skew") is an internal product identifier used by a retailer for inventory, pricing, and reporting. It’s distinct from UPC: the UPC is assigned by the manufacturer and is universal across stores; the SKU is whatever the retailer decides.

SKU formats vary wildly. Walmart uses 9-digit numerics. Costco uses 5-7 digits (with leading 1 for grocery, 9 for non-food). Best Buy uses 7-8 digits. Home Depot uses 11-12 digits. Sephora uses long alphanumeric SKUs that include shade codes.

On receipts, SKUs appear in two places: the item-line (Costco prints the SKU prominently, Walmart hides it), and in the item description in some retailers (Apple Store hardware shows the model number, which is essentially a SKU).

For receipt design, choosing the right SKU format for the brand you’re replicating is one of the most consequential authenticity details. A Costco receipt with Walmart-style 9-digit SKUs reads as fake immediately.