Free shipping: where to set the threshold

Set the free-shipping threshold where contribution margin covers courier and packaging: at 32% margin, 5.90 euro for the courier and 0.85 euro for packaging, break-even is a 21.09 euro cart. Any higher threshold is a commercial choice, not a saving, and should be measured as one.

Free shipping is not free, it is a discount

The seller always pays the courier, so free shipping is a discount equal to the shipping cost, applied to anyone above the threshold. The right question is not "how much does the average cart rise" but "how much margin do I give away on people who would have bought anyway". If 70% of orders already clear the threshold with no incentive, that threshold moves nothing and costs the full shipping on that group.

The arithmetic, in a table

The table says two things. First, below 21.09 euro free shipping sells at a loss, and every small cart given away eats the margin of ten large ones. Second, the threshold is not a number to copy: it is the point where the fixed cost per order is already paid.

Where the threshold has to be written

Article 49(1)(e) of the Consumer Code and Article 6(1)(e) of Directive 2011/83/EU require the consumer to know the total price, delivery included, before being bound. In practice: the threshold belongs on the product page, in the cart and in the first checkout step, with the exact charge below it. A bar that says "12 euro to go" without saying what shipping costs if you stop short is a cost that appears at the end, and costs that appear at the end are the first cause of abandonment.

Redo the sum per weight band

One average margin hides the product that costs 9 euro to ship because it weighs 4 kg. Redo the sum for three weight bands and two product categories: if one threshold holds everywhere, keep it; if not, the answer is a stepped threshold (free above 49 euro for the light category, above 89 euro for the heavy one) or a fixed contribution. The snippet below redoes the sum in a second when the courier changes its price.

node -e "const ship=5.9,pack=0.85;for(const m of [0.24,0.32,0.40]){const be=(ship+pack)/m;console.log('margine',(m*100).toFixed(0)+'%','pareggio',be.toFixed(2)+' euro')}"

The test worth more than the arithmetic

Set the threshold at break-even for two weeks and record three numbers: average cart, share of orders above the threshold, margin per order. Then raise the threshold by 30% for another two weeks on the same traffic. If margin per order grows and order count drops by less than 5%, the higher threshold is justified; otherwise you are just steering customers towards the smaller cart. Measure margin, not revenue, because free shipping always raises revenue.

The limitation

These numbers hold for the stated inputs: 32% margin, 5.90 euro courier, 0.85 euro packaging. A shop at 18% margin breaks even at 37.50 euro, one at 45% at 15 euro. The sum also ignores two real effects: free shipping raises returns, because people who buy to reach a threshold send things back more often, and it raises average parcel weight. Measure both on your own history before fixing the number.

Where to start