The price a customer pays for an online order is not the amount a seller keeps. Between checkout and settlement sit commissions, fees, shipping, payment charges, advertising and the cost of orders that come back. For many sellers, the profit on a sale is decided less by the product than by how these deductions stack up.
The deductions, in order
Marketplace commission is typically a percentage of the selling price that varies by category. Platforms often add fixed fees per order, closing fees or fees linked to the price band.
Fulfilment and shipping charges depend on the item's weight, dimensions and the distance travelled. Shipping is generally calculated on the greater of actual and volumetric weight, so a light but bulky product can cost more to ship than its weight suggests. Sellers using a marketplace's warehouses also pay storage and handling, and storage costs rise for slow-moving stock.
Payment and collection costs include gateway charges and, for cash-on-delivery orders, collection fees.
Customer acquisition covers sponsored listings and other advertising. For newer brands this is often the largest variable cost and the one least visible in a simple margin calculation.
Taxes also matter. GST applies to the product and separately to platform fees, and tax collected at source by marketplaces affects the seller's cash flow even when it is later recoverable.
Returns change the picture
A returned order can cost the seller twice. The forward shipping and fees may not be refunded, and reverse logistics adds another charge. The returned item may need inspection and repackaging, may be resaleable only at a discount, or may be unsaleable. Categories with high return rates, such as fashion and footwear, carry this cost on a large share of orders.
Return-to-origin orders, where the customer refuses delivery, are a related cost common with cash on delivery. The product travels to the customer and back without ever being sold.
Building an honest view of each online order
The useful measure is contribution margin per order: selling price, minus product cost, minus every variable deduction, with return costs spread across all orders in line with the return rate. Sellers who calculate only gross margin tend to overestimate profit, often by enough to change which products deserve investment.
Platform settlement reports provide most of the inputs, though fee structures change and reconciling them takes work. Sellers who reconcile every month can spot fee changes, incorrect weight charges and unexplained deductions early.
The decision that follows is about the catalogue. Once contribution margin is visible by product, some best-sellers turn out to lose money after returns and advertising. Repricing them, redesigning packaging to cut volumetric weight, or dropping those lines may do more for profit than growing sales.
Questions this story answers
What fees reduce a seller's margin on an online marketplace order?
Marketplace commission, fixed or closing fees, fulfilment and shipping charges, storage and handling for marketplace warehouses, payment gateway and cash-on-delivery collection fees, advertising and GST on platform fees. Tax collected at source also affects cash flow even when recoverable.
What is volumetric weight in e-commerce shipping?
Shipping is generally calculated on the greater of actual weight and volumetric weight, which reflects an item's dimensions. A light but bulky product can therefore cost more to ship than its weight suggests, and redesigning packaging can reduce that charge.
How do I calculate contribution margin per online order?
Take the selling price, subtract product cost and every variable deduction, including commission, fees, shipping, payment charges and advertising, and spread return costs across all orders in line with the return rate. Platform settlement reports provide most of the inputs.
