Breakeven ROAS

Breakeven ROAS is one divided by contribution margin. A store keeping 40% of each order after product cost, shipping, fees, and a returns allowance breaks even at 2.5 (1 ÷ 0.40). At 25% margin it is 4.0. At 60% it is 1.67. Every campaign reporting below that line is losing money on each conversion it presents as a win, and the dashboard will look no different.

Work an order through to see where the margin actually goes. A $120 order: $48 product cost, $9 shipping and fulfillment, $3.50 payment fees, and a 6% returns allowance at $7.20. That leaves $52.30, or 43.6% contribution margin, so breakeven ROAS is 2.29 and breakeven CPA is $52.30. Notice that returns and fees together took nearly nine points of margin — the two lines most often left out of a quick calculation, and the two that turn a 2.0 target from comfortable into underwater.

The most consequential mistake is computing one breakeven for the whole account, usually from the flagship product, then governing the entire catalog with it. Margins vary across a catalog by twenty points or more, so a single account-wide figure is simultaneously too strict for the high-margin range and too generous for the low-margin one. It hides its own error: aggregate performance can sit exactly on target while the mix underneath is a profitable half subsidizing a loss-making half.

The fix is margin bands rather than per-SKU precision. Group the catalog into three or four bands, compute breakeven for each, and set campaign targets from the band a campaign actually sells. Feeding banded margin values to the platforms as conversion values — the POAS approach — pushes the same logic into bidding, so the algorithm stops treating a 60%-margin sale and a 20%-margin sale as equivalent.

Breakeven is a floor, not a target. Sitting on it means advertising has paid for itself and contributed nothing to overhead or profit. The target is breakeven plus the margin you intend to keep, and the gap between the two is a business decision about how much of your contribution you are willing to convert into growth. A business deliberately buying market share may run close to breakeven for a period; one funding its own operations from cash flow cannot.

Rebase quarterly, with finance in the room. Supplier prices move, shipping rates move, return rates move seasonally, and a breakeven computed once at the start of a year silently misprices every decision made against it by month nine.