How To Calculate Your True Cost Per Ecommerce Order

Knowing what each order costs helps you set prices, evaluate advertising and understand which products are worth promoting. The useful number is not simply the supplier price: it includes the variable costs triggered by fulfilling the order.

Start with a consistent definition

For unit economics, define cost per order as the product costs plus variable fees, packaging, and fulfillment expenses associated with that order. Keep advertising separate at first so you can see contribution before and after acquisition cost.

What to do: Include marketplace commissions where applicable. Do not mix business-wide rent or fixed software subscriptions into variable cost per order without labeling them as allocated overhead.

Calculate contribution before advertising

Take net revenue associated with the order, excluding sales tax collected on behalf of tax authorities, and subtract variable order costs. If the customer paid a shipping charge, treat it consistently as part of order revenue while including the actual shipping expense.

What to do: Formula: Order contribution before ads = net order revenue − product cost − variable fulfillment cost − variable fees.

Then account for acquisition

Advertising spend is rarely traceable perfectly to one order. Divide campaign spending by attributed new orders for a rough acquisition-cost estimate, but interpret attribution carefully. Organic and repeat purchases should not be assigned the same acquisition cost automatically.

What to do: Review blended marketing spend across all orders alongside platform-reported return on ad spend. Both perspectives reveal different things.

Compare products on a common basis

A $150 product can generate less contribution than a $75 product if shipping, fees and returns are much higher. Compare contribution in dollars and as a percentage of revenue; both matter.

What to do: Use the same date range, tax treatment, refund treatment and cost assumptions across products.

Update costs when conditions change

Supplier increases, dimensional-weight shipping fees and changes in processing charges make static spreadsheets stale. Updating your assumptions monthly is more useful than a precise calculation based on old numbers.

What to do: Set a recurring review date and save the assumptions you used.

A practical example

Example: $120 net order revenue minus $48 product cost, $13 fulfillment, $6 transaction fees and $3 packaging leaves $50 before ads. If estimated acquisition expense is $32, contribution after ads is $18, before fixed overhead and taxes.

Your next step

Use your latest order data and calculate one real order from start to finish. Then compare the result with the break-even ROAS guide.

Explore related WiseLivn guides: Shopify Sales vs. Profit, Break-Even ROAS, and 13-Week Cash Flow Forecast.