Amazon are now using your packaged product’s dimensions and unit weight to determine its size tier for Pan-European FBA, European fulfilment network, Multi-Channel fulfilment fees, and customer returns processing fees. This they say is to better align Amazon fees with fulfilment costs for all parcels size bands excluding Small and Light items.
To determine your product’s weight tier, Amazon will use the greater of the unit weight or the dimensional weight in kilograms, calculated as (length x width x height cm3) divided by 5,000.
Loose packaging is counted towards the packaged product’s dimensions for fee calculations. Therefore Amazon recommend that you minimise the dimensions of deformable packaging by using tight-fitting or vacuum-sealed poly bags or taped flaps.
This also has significance on how you present products, for instance, rolling jeans rather than supplying flat folded should reduce the dimensional weight, similarly, supplying a football or basketball flat rather than inflated will also reduce fulfilment costs. Anything that can be supplied effectively flat packed, especially items which are bulky but lightweight, offers the potential to reduce Amazon fulfilment fees simply by changing the format which the item is packaged.
This fee adjustment for packaged product’s dimensions marks design considerations that you should consider right back to the manufacturing process rather than simply address at the point of preparing shipments to Amazon.
Amazon will continue to use unit weight only to determine the shipping weight of envelopes, Small and Light items, and special oversize items.