A target ROAS number usually gets picked once, in a spreadsheet, early on — and then treated as a fixed marketing setting for years, even as margin, average order value and acquisition cost quietly drift underneath it.
The math nobody actually checks
Break-even ROAS is 1 ÷ contribution margin. A store running 40% margin breaks even at 2.5x ROAS; a store running 20% margin needs 5x just to break even. Two businesses can run the same target ROAS and be nowhere near equally profitable, because the target was never actually derived from their own margin.
Platform revenue isn't your revenue
The revenue figure a platform reports against a campaign usually includes tax, shipping charged to the customer, and pre-discount pricing — none of which is money you keep. A campaign hitting its ROAS target on paper can still be unprofitable once that revenue is corrected down to what actually lands in the bank.
Blended margin hides the products carrying the account
A single account-wide ROAS target, applied uniformly across every product and campaign, means the products with real margin are held to the same bar as the products with almost none. Splitting the target by product margin band routinely finds spend that should be reallocated, not just spend that should be cut.
When to actually change it
Margin shifts (a cost increase, a pricing change, a new discount tier), average order value shifts, and the cost of acquiring a customer through other channels all move the correct target. None of these show up automatically in a platform's dashboard — they have to be brought in from outside it, deliberately, on a schedule.
Where to start
- Calculate break-even ROAS from real contribution margin, not a round number
- Strip tax, shipping and discounts out of platform-reported revenue before judging it against target
- Split target ROAS by product or category margin band if the mix varies meaningfully
- Put a recurring date on the calendar to revisit the target, not just the spend
Treated this way, target ROAS stops being a marketing setting and becomes what it actually is — a margin decision, recalculated on a schedule instead of set once and forgotten.