How breakeven ROAS is calculated
ROAS (return on ad spend) is revenue divided by ad cost. A 3× ROAS means $3 of revenue for every $1 of ads. The problem: revenue is not profit. Your breakeven point depends on how much of each order survives after product, fee and shipping costs — your contribution margin.
A store keeping 40 cents of every revenue dollar breaks even at 1 ÷ 0.40 = 2.5×. A store keeping 25 cents needs 4.0×. Same platform, same ads, wildly different survival thresholds — which is why copying a competitor’s “target ROAS” without knowing their margins is a coin flip.
A worked example
Your average order is $60. Product costs are $22, platform and payment fees run $7.50, and fulfillment is $6. That leaves $24.50 per order — a 40.8% contribution margin.
Every campaign running below 2.45× is losing money, even the ones the dashboard paints green. And breakeven is not the goal — it is the floor. If you want to keep 10% of revenue as profit after ads, you can only spend 30.8% of each order on acquisition, pushing the required ROAS to about 3.24×.
Breakeven ROAS by margin — a reference table
| Contribution margin | Breakeven ROAS | ROAS for 10% profit |
|---|---|---|
| 25% | 4.00× | 6.67× |
| 35% | 2.86× | 4.00× |
| 45% | 2.22× | 2.86× |
| 55% | 1.82× | 2.22× |
| 65% | 1.54× | 1.82× |
The pattern is unforgiving at the low end: dropping from 35% to 25% margin raises your breakeven from 2.86× to 4.0×. Margin improvements are usually worth far more than campaign optimizations — a lesson the profit margin calculator makes concrete.
Three mistakes that make breakeven ROAS lie to you
Using gross AOV with a sitewide discount running. If 20% off is live, your real revenue per order is lower than the dashboard AOV. Calculate with post-discount numbers.
Ignoring returns. If 8% of orders come back, roughly 8% of your “revenue” evaporates after the ROAS was recorded. Bake an allowance into your per-order costs for return-heavy categories like apparel.
Judging prospecting by first-order profit alone. If repeat purchase rates are strong, running new-customer campaigns at breakeven — or slightly below — can be rational. But that is a deliberate LTV decision, not an excuse to skip the math.
FAQ
What is breakeven ROAS?
Breakeven ROAS is the return on ad spend at which a campaign makes exactly zero profit. It equals 1 divided by your contribution margin. If you keep 40% of each order after product, fee and shipping costs, your breakeven ROAS is 1 ÷ 0.40 = 2.5×. Below that, every conversion loses money; above it, ads contribute profit.
What is a good ROAS for ecommerce ads?
There is no universal good ROAS — it depends entirely on your margin. A 3× ROAS is fantastic for a store with 55% contribution margin (breakeven 1.8×) and a money-loser for a store with 25% margin (breakeven 4×). Calculate your breakeven first; a good ROAS is meaningfully above it.
Why is my campaign losing money at a 2.5× ROAS?
Because ROAS measures revenue, not profit. If your combined product, fee and shipping costs consume more than 60% of each order, a 2.5× ROAS sits below your breakeven point. The ad platform dashboard will still show it in green — the platform does not know your costs.
Should breakeven ROAS include new-customer discounts?
Yes. If a first-purchase discount takes 10% off the order, either lower your AOV input to the discounted amount or add the discount as a per-order cost. Otherwise your breakeven will look easier than it really is, and prospecting campaigns will quietly bleed.
How does breakeven ROAS relate to CPA?
They are two views of the same limit. Your maximum CPA (cost per acquisition) is the dollars left after all per-order costs; breakeven ROAS is order value divided by that number. Some ad platforms optimize better against a CPA target, so the calculator shows both.