E-Commerce
Most e-commerce operators confuse gross margin with actual profit. This guide shows every cost layer that sits between the sale price and money in your pocket.
Gross margin only subtracts COGS. It ignores shipping, platform fees, ad spend, and return costs — all of which are directly tied to each order. An operator running 40% gross margin can be losing money on every order once the full picture is accounted for.
True profit is the number that matters. Everything else is a partial view.
1. COGS
Product cost, packaging, manufacturing
$18.00 on a $79 product
2. Fulfillment
Shipping, warehousing, pick + pack
$8.50 average for sub-1lb domestic
3. Platform fee
% of sale: Shopify 2.9%, Amazon 8–15%
$2.77 at 3.5% on $79
4. Ad spend
Paid traffic cost per converted order
$12 if ROAS is 6.5×
5. Return reserve
% of orders × partial refund cost
$1.98 at 5% return rate, 50% recoup
True Profit = Sale Price
− COGS
− Shipping + Fulfillment
− Platform Fee (% of sale)
− Ad Spend per Order
− Return Reserve (sale × return rate × 0.5)
= True Profit per Order
Margin supports ad spend increase and can absorb cost fluctuations. Scale confidently.
Workable with tight operations but vulnerable to shipping rate increases, ROAS compression, or return spikes.
Any cost movement makes the unit unprofitable. Reprice, cut ad spend, or reduce COGS before scaling.
You are paying for customers. Every incremental order destroys cash. Do not run ads on negative-margin products.
ROAS breakeven tells you the minimum return on ad spend required to not lose money on ads. Below this number, you are paying to lose.
ROAS Breakeven = Sale Price ÷ Ad Spend Per Order
Example: $79 ÷ $12 = 6.58×
Any campaign returning below 6.58× ROAS is unprofitable at this cost structure.