IPMP

Inner Packs Per Master Pack (IPMP) is a logistics and packaging term used by Amazon and vendors to define how inventory is structured for shipping and storage. It represents how many inner packs - each containing multiple retail units - are packed together inside one master pack (or master carton).

Hierarchy of packaging:

• Retail unit – individual item for sale
• Inner pack – group of retail units (e.g. 6 bottles of shampoo)
• Master pack – box containing multiple inner packs (e.g. 4 inner packs)

So if each inner pack has 6 units, and there are 4 inner packs in a master pack, the IPMP = 4, and the total units per master carton = 6 × 4 = 24.

Why IPMP matters:

• Required in Amazon’s carton and PO data templates
• Ensures accurate inventory receiving and barcode scanning
• Impacts freight planning, pallet configuration, and warehouse efficiency
• Reduces overages, shortages, or packaging violations that lead to chargebacks

💡 Example: A vendor lists IPMP as 5 in their PO, meaning each master carton should contain 5 pre-packed inner packs - Amazon will reject shipments that don’t match this structure.

In short:
IPMP defines how many inner packs go into each master carton - a key part of compliant and efficient packaging for shipping to Amazon’s fulfilment centers.