The ROAS in your panel can hide the fact that you are losing money. How to calculate break-even ROAS, which threshold turns advertising into a loss, and how to manage campaigns weekly.
The ROAS shown in a marketplace ad panel can make an unprofitable campaign look excellent — because it ignores commission, cost of goods and shipping. This article shows how to calculate your own break-even ROAS, which threshold turns advertising into a loss, and how to manage campaigns week by week.
The sentence marketplace sellers repeat most often: "ROAS is 5, we're doing well." The same seller reaches month end, sees revenue up and the bank balance flat. The reason is simple: ROAS is not a profitability metric, it is a revenue metric.
ROAS and ACoS: two sides of one number
- ROAS = ad revenue ÷ ad spend. "I spent 1 TL and made 5 TL of revenue" → ROAS 5.
- ACoS = ad spend ÷ ad revenue. The same example is 20%.
The relationship is simply ACoS = 1 ÷ ROAS. Marketplace panels usually speak in ACoS, Google and Meta in ROAS; both say the same thing. What matters is not which one you use, but which threshold you read it against.
Why the panel's ROAS misleads
The panel shows the revenue attributed to your ad spend. What that revenue figure does not account for:
- Category commission and the VAT on top of it
- Fixed per-order service fees
- Shipping cost
- Cost of goods
- The cost of your return rate
So ROAS 5 means "I generated five times what I spent in revenue" — not "I made five times the profit". Depending on how much of that revenue survives the deductions, ROAS 5 can easily be a loss.
Break-even ROAS: the number you should actually watch
Break-even ROAS is the point where advertising neither makes nor loses money. The formula is one line:
Break-even ROAS = 1 ÷ Contribution margin rate
The contribution margin rate is the share of the sale price left after every deduction except advertising. The equivalents:
| Contribution margin before ads | Break-even ROAS | Break-even ACoS |
|---|---|---|
| 10% | 10.0 | 10% |
| 15% | 6.7 | 15% |
| 20% | 5.0 | 20% |
| 25% | 4.0 | 25% |
| 30% | 3.3 | 30% |
| 40% | 2.5 | 40% |
Read it like this: if your contribution margin is 15%, ROAS 5 is a loss. You need 6.7 just to break even. The seller celebrating a "5" in the panel is losing a little money on every unit sold.
Work out your own number
Continuing from our earlier article on commission and profit margin: a 600 TL item in a 20% commission category with a cost of goods of 300 TL:
| Sale price | 600.00 TL |
| Commission + VAT | −120.00 TL |
| Shipping | −77.54 TL |
| Cost of goods | −300.00 TL |
| Return allowance (10% return rate) | −15.50 TL |
| Contribution margin before ads | 86.96 TL → 14.5% |
|---|---|
| Break-even ROAS | 6.9 |
On this product your target is not ROAS 5 but at least 6.9. To actually make money you should be aiming at the 8–9 band. A campaign run on the assumption that "ROAS 5 is good" grows revenue while shrinking profit.
Organic cannibalisation: the invisible line that inflates ROAS
Not every order attributed to an ad is an order that would not have arrived anyway. On products where you already hold the Buy Box, where customers search for your brand by name, or where you rank first organically, advertising simply charges you for a sale you were going to get.
A practical test: switch a product's campaign off for two weeks and look at total units sold. If total sales did not drop noticeably, that campaign was not creating revenue — it was booking organic sales to the ad column. ROAS measured without this test always reads higher than the truth.
Campaign design: what deserves advertising
- Is the contribution margin sufficient? Below 10%, advertising is mathematically hard; fix price or cost first.
- Does the product page convert? Sending traffic to a product with few reviews and weak images means paying for clicks that will not convert. Fix the product page first.
- Is there enough stock? Running out mid-campaign burns both budget and seller score.
- Do you hold the Buy Box? Advertising a product where you do not can make the sale for your competitor. For how the Buy Box works, see our Trendyol and Hepsiburada guides.
If you cannot answer yes to all four, the problem with that product will not be solved by advertising.
A weekly optimisation rhythm
- Compare each product's ROAS against its own break-even threshold. Do not manage with a single target ROAS; every product has a different threshold because every product has a different margin.
- Throttle campaigns below the threshold before switching them off. Make the off decision on two weeks of data.
- Increase budget where you are comfortably above it. A campaign running at ROAS 12 represents sales lost to an insufficient budget.
- At month end, compare total ad spend against total gross profit. Tables that look positive campaign by campaign and negative in total are common.
Common mistakes
- Applying one target ROAS to every product. An 8% margin item and a 35% margin item cannot share a threshold.
- Treating advertising as a separate marketing budget. Marketplace advertising is a cost of sale and belongs in the margin.
- Trying to rescue a low-converting page with ads. Traffic magnifies a conversion problem; it does not solve it.
- Optimising daily. Marketplace data swings day to day; decide on at least a week of data.
- Never measuring cannibalisation. Without the switch-off test, no campaign's real contribution is known.
Conclusion
In marketplace advertising the right question is not "what is my ROAS" but "what is my break-even ROAS on this product, and am I above it". A seller who calculates that threshold product by product makes materially more profit on the same budget — because the money moves to the products that were already earning.
At Commerslab we make advertising decisions against this threshold table for the stores we manage, collecting commission and shipping data automatically through our integrations. See our marketplace management service or request an assessment of your campaigns.
The rates and methods in this article are a general framework; calculate your own contribution margin using the current commission, shipping and return figures in your seller panel.
