The dashboard says "ROAS 4x" and everyone is pleased. Yet depending on your margin, that same campaign may be making money — or quietly losing it. ROAS measures revenue; ROI measures profit. That single difference is why many companies keep funding the wrong campaign.
What is ROAS?
ROAS (Return on Ad Spend) is the ratio showing how much revenue each unit of ad spend produced. The formula is simple: ROAS = Revenue from ads ÷ Ad spend. Spend 50,000 and make 200,000 in revenue and your ROAS is 4x. The ratio ignores your costs, returns and profit margin; it compares revenue to spend, nothing more.
What is ROI?
ROI (Return on Investment) is the return expressed in profit: ROI = (Gross profit − Ad spend) ÷ Ad spend × 100. In the same example, a 40% gross margin turns 200,000 revenue into 80,000 gross profit; subtract the 50,000 spend and 30,000 is left. ROI is 60%. A ROAS of 4x sounds impressive, while the real return is far more modest.
Why does the difference matter?
ROAS is misleadingly optimistic in high-margin businesses and dangerously reassuring in low-margin ones. For a software company at 85% margin, 2x ROAS means profit; in food retail at 20% margin, 4x ROAS is still a loss. The same number means opposite things in two businesses.
So when an agency report shows ROAS alone, the first question to ask is: what is our break-even ROAS?
Break-even ROAS: one formula
Break-even ROAS is the threshold at which a campaign neither profits nor loses, and it is a single division: Break-even ROAS = 1 ÷ Gross margin. Every campaign below that threshold loses money while growing revenue.
| Gross margin | Break-even ROAS | Target for profit |
|---|---|---|
| 20% | 5.00x | 7.5x and above |
| 30% | 3.33x | 5.0x and above |
| 40% | 2.50x | 3.8x and above |
| 50% | 2.00x | 3.0x and above |
| 60% | 1.67x | 2.5x and above |
| 80% | 1.25x | 1.9x and above |
The "target" column is roughly 1.5 times break-even, a safe band that also absorbs operations, logistics and returns.
A worked example
Picture an e-commerce brand: 80,000 monthly ad spend, 320,000 revenue from ads, 35% gross margin, 160 new customers.
- ROAS: 320,000 ÷ 80,000 = 4.0x
- Break-even ROAS: 1 ÷ 0.35 = 2.86x → threshold cleared
- Gross profit: 320,000 × 0.35 = 112,000
- Net contribution: 112,000 − 80,000 = 32,000
- ROI: 32,000 ÷ 80,000 × 100 = 40%
- Customer acquisition cost (CAC): 80,000 ÷ 160 = 500
The campaign is profitable, but drop the margin two points or raise ad costs 15% and the picture moves quickly towards break-even. Someone watching ROAS cannot see that fragility; someone watching ROI can.
Five common mistakes
- Not deducting returns and cancellations. Platform revenue is gross. With a 15% return rate, true ROAS sits roughly 15% below the dashboard figure.
- Treating margin as a single number. Margin differences between product groups decide campaign profitability in advance; calculate by category.
- Charging brand spend to performance. An awareness campaign's return does not appear in the same month's sales. Brand and performance budgets must be measured separately.
- Ignoring repeat purchase. A campaign that breaks even on the first order is actually profitable when customer lifetime value is high. The measure is not the first order alone.
- Forgetting the attribution window. The gap between a 7-day and a 30-day window can make the same campaign look successful or failed. Fix the window, then compare.
Which metric, when?
- Campaign optimisation: ROAS. Fast, platform-native, good for daily decisions.
- Budget decisions: ROI. Profit decides which channel gets more money.
- Growth planning: CAC and customer lifetime value. How much of the cost of acquisition comes back, and when?
At Circle we read three numbers together in media reports: ROAS, break-even ROAS and net contribution. The first shows campaign efficiency, the second the threshold, the third the money left in the business. Read apart, "successful" campaigns tend to reappear at year end as the line items dragging profit down.
Frequently asked questions
What is a good ROAS?
There is no single correct number; it depends on your margin. At 40% margin, 2.5x is break-even and 3.8x is healthy. That same 3.8x is a loss in a 20% margin business.
What if ROAS falls while revenue grows?
That can be the natural result of scaling. If net contribution keeps growing there is no problem; when net contribution starts to fall, pause the scaling or narrow the targeting.
How is the ROI of brand campaigns measured?
Not through direct sales, but through branded searches, direct traffic, assisted conversions and a falling CAC over time. The measurement window is longer than for performance campaigns.
Should VAT be deducted from revenue?
Yes. Always calculate on revenue and costs excluding VAT; otherwise ROAS looks higher than it is.
Next step
Enter your own numbers into the ROI / ROAS calculator on our site: type in spend, revenue, margin and customer count to see ROAS, ROI, net profit, CAC and break-even ROAS together — and know at once whether the campaign is genuinely profitable.
