Return on ad spend (ROAS) is the revenue a campaign credits to itself divided by what it spent. Spend 10,000, record 40,000, and ROAS is 4. The number measures revenue and knows nothing about what your product costs you, so it can sit high while the month loses money.
This article shows how to calculate your own break-even point, and gives you a table that ties each ad metric to profit and the decision it should drive.
A hypothetical example: ROAS of 4 and a loss at month's end
A hypothetical store sells a product at 1,000, in generic currency units:
| Item | Value |
|---|---|
| Selling price | 1,000 |
| Product cost | 550 |
| Shipping | 90 |
| Payment fees and returns | 60 |
| Left from each sale before marketing | 300 (30% margin) |
| Ad spend | 10,000 |
| Recorded sales (40 units) | 40,000 |
| ROAS | 4 |
| Left from 40 units | 12,000 |
| After ad spend | 2,000 |
| After campaign management (3,000) | 1,000 loss |
A 4 looks excellent to anyone reading the ad dashboard alone. The month's statement disagrees.
Calculate break-even before you read ROAS
Break-even ROAS is the point where you neither gain nor lose. It has two forms, and you need both:
Ad break-even = 1 ÷ margin before marketing
In our example: 1 ÷ 0.30 = 3.33. Anything below that loses money from the first sale, before any other cost.
Full break-even = (spend + fixed marketing costs) ÷ (spend × margin)
In our example: (10,000 + 3,000) ÷ (10,000 × 0.30) = 4.33. This store needs a ROAS of 4.33 to avoid a loss at this spend, which is why 4 lost money.
Work it out for each product or category. A product with a 60% margin breaks even at 1.67, and one with a 20% margin needs 5, even when both run in the same campaign.
Why the ROAS in the platform can mislead you
Even before margin, the number is an estimate, since each platform counts revenue under its own attribution rules. The platforms' total can exceed your real sales. That's why the work starts by reconciling platforms with your sales system, as explained in how to measure conversions after the privacy changes.
The problem grows when the number becomes a bidding target. Google Ads lets you set a percentage target such as 300%, and asks for at least 15 conversions in the last 30 days when using it, per the Google Ads Help Center. Enter a target that isn't based on your margin and you're asking the algorithm to hit a number that may lose money.
A table that ties ad metrics to profit
Check this table before any decision to raise or cut a budget:
| Metric | What it says | Link to profit | The decision it helps with |
|---|---|---|---|
| ROAS | Recorded revenue per unit of spend | Blind to costs | Comparing campaigns inside one platform |
| Break-even point | The lowest acceptable return | Direct | The floor for running a campaign |
| Cost per new customer | What you pay for someone who hasn't bought before | Set against customer profit | Continuing or scaling |
| New-customer share | How much revenue came from new customers | An existing customer may have bought without the ad | Separating campaigns aimed at current customers |
| Average order value | Basket size | Each increase lowers cost relative to revenue | Offers and bundles |
| Repeat purchase rate | How often customers buy in a period | Allows a lower return on the first order | How much first-sale loss you accept |
| Return rate | What comes back after the sale | Reduces revenue and profit | Calculating ROAS after returns |
| Payback period | When the money comes back | A matter of cash | How much scaling you can fund |
Three corrections that change the verdict
Take returns out of revenue. In a hypothetical campaign with a ROAS of 4, if 15% of orders come back, the real figure is 3.4. Profit falls further if you pay shipping twice.
Separate new customers from current ones. A campaign returning 6 from current customers may be taking credit for sales that would have happened anyway, while one returning 2.5 from new customers may matter more for growth if they buy again. Judge after counting repeat purchases. For that part, use the method in customer acquisition cost.
Separate cash from profitability. A campaign may profit after a year of repeat orders, but your company may not be able to wait. Work out how many months your money stays out before sales bring it back.
The monthly report an owner needs
Ask for this line per campaign, in place of a table crowded with clicks and impressions:
- Spend and revenue confirmed by the sales system.
- What's left after product cost, shipping and fees.
- Revenue after returns.
- New customers and the cost of each.
- Net profit after ads and management fees.
- The decision: raise, keep or stop, with its reason.
If you sell services or to other companies, and sales happen weeks after the lead, use closed deal value in place of revenue recorded in the platform, and wait for your usual selling period to end. Our article on digital marketing for companies places these numbers on the path from spend to profit.
Common questions
What's a good ROAS? There's no general number, because the answer comes from your margin. A good one clears your full break-even by enough to deliver the profit you want.
Should I drop ROAS entirely? No. It's handy for quick comparisons between similar campaigns inside a platform. Use it for comparison and make the budget decision from profit.
Next step
Take the product you advertise most, work out its true margin and full break-even, and compare them with the last 30 days' ROAS. If you'd like someone to build this report from your sales figures and tie it to budget decisions, take a look at PlanKit's digital marketing and campaigns service.