SKU (Stock Keeping Unit) in Packaging and Inventory Management

What Is a SKU?

A Stock Keeping Unit, or SKU, is a unique alphanumeric code that identifies a specific product or item in an inventory management system. In the context of packaging, each distinct box size, style, print variation, or material configuration typically receives its own SKU. This allows businesses to track inventory levels, monitor usage rates, manage reorder points, and control costs for each individual packaging item.

SKUs are created and managed by the buyer or user of the packaging, not by the manufacturer. They are internal to your organization’s inventory and procurement systems, though you may share them with your packaging supplier to streamline communication and order processing.

SKU vs. SPEC# vs. UPC

It is important to distinguish between a SKU, a specification number (SPEC#), and a UPC (Universal Product Code). Your SKU is your internal inventory identifier. The SPEC# is the manufacturer’s design identifier that captures the complete production specifications for a box. The UPC is a standardized barcode used for retail scanning and supply chain identification.

A single corrugated box design may have one SPEC# at the manufacturer but correspond to multiple SKUs in the buyer’s system (for example, if the same box is stocked at different warehouse locations). Conversely, a product with one SKU in your system may require a box with a specific UPC printed on it for retail compliance.

Why SKUs Matter for Packaging Procurement

Maintaining well-organized packaging SKUs allows your procurement team to track consumption, forecast demand, and avoid stockouts. When you know exactly how many units of each box SKU you use per week or month, you can plan production runs and blanket orders more effectively. This reduces emergency orders, which typically carry higher per-unit costs due to shortened run lengths and expedited setup.

For companies managing dozens or hundreds of packaging items, SKU rationalization — the process of reviewing and consolidating packaging designs — can yield significant savings. Reducing the number of unique box sizes in your program means fewer dies, fewer setups, and potentially higher quantities per remaining SKU, all of which lower cost.

Working with President Container Group

When you provide your packaging SKU numbers alongside the corresponding SPEC# in your purchase orders, it creates a clear link between your internal systems and our production records. This minimizes order errors and speeds up processing, especially for repeat orders. Our team at President Container can work with your procurement and operations teams to establish efficient ordering workflows tied to your SKU structure.

For businesses that need assembly and fulfillment services, our Tech-Pak division manages packaging components by SKU through the assembly process, ensuring the right boxes, inserts, and materials come together accurately for every order.