Setting up your costs
What is a packaging composition?
The materials one parcel is made of, by weight: so many grams of paper or cardboard, so many of plastic. It is entered once as the shape of a typical parcel and drives two things: the packaging cost per order, and the packaging EPR fee where you owe one.
It is deliberately a composition rather than a per-parcel measurement. Weighing every box would be more precise and impossible to maintain, and the fee is charged on the mass of material placed on a market, which a representative composition captures well.
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