If your ROAS target is green but your bank balance keeps falling, the problem is almost always the same: your ROAS target was set without accounting for your full cost structure. Here is the math that shows why, and how to calculate the number you should actually be hitting.

The situation you recognise

You check the Google Ads dashboard, ROAS is sitting comfortably above your target, and yet when the credit card statement arrives at the end of the month there is less money in the account than there was thirty days ago. The number that was supposed to tell you whether ads are working is green, and the business still feels like it is bleeding.

Why ROAS misleads you: a worked example

Say your store does $80,000 in monthly revenue from ads. Your cost of goods sold is 55% of revenue, so $44,000 leaves immediately. Shipping runs $6 per order and you shipped 1,000 orders, another $6,000 gone. Payment processing and marketplace fees add roughly 3%, which is $2,400. Ad spend for the month was $16,000. Add those four buckets: $44,000 + $6,000 + $2,400 + $16,000 = $68,400 in total outflows. Revenue minus outflows is $80,000 – $68,400 = $11,600 gross contribution, and that is before you pay yourself, your warehouse staff, software subscriptions, or returns.

Now look at what ROAS said: $80,000 revenue divided by $16,000 ad spend = 5.0x. A 5x ROAS sounds excellent. But your true product margin after COGS, shipping, and fees, before ads, is only ($80,000 – $44,000 – $6,000 – $2,400) divided by $80,000 = 34.5%. To break even on ad spend alone, you need ROAS = 1 / 0.345 = 2.9x. You cleared that easily, so why is the account thin? Because that 34.5% margin must also cover every other fixed and variable cost in the business. If overhead eats another 20 points, your real available margin before ads is closer to 14.5%, and break-even ROAS jumps to 1 / 0.145 = 6.9x, well above the 5x you were celebrating.

What this means for your next decision

A ROAS target set without knowing your full-cost margin is a guess. In the example above, running at 5x while needing 6.9x to break even means every dollar of ad spend is spending money the margin does not cover. Cutting spend or raising prices may feel counterintuitive when ROAS looks healthy, but the math says one of those levers must move.

How to calculate your real break-even ROAS

Pull four figures. Revenue comes from Google Ads: Reports, then the predefined Products report, or just the campaign-level Conversion Value column for the period. Ad spend is in the same report, Cost column. COGS and variable costs come from your accounting software (QuickBooks, Xero): look for Cost of Goods Sold and Fulfillment Expense line items for the same date range. Fees come from your Shopify Payments or Stripe dashboard, monthly fee summary.

Divide (Revenue – COGS – Shipping – Fees) by Revenue to get your true pre-ad margin percentage. Then divide 1 by that percentage. That is your real break-even ROAS. Compare it to what your campaigns are actually delivering.

One call can tell you which lever to pull

If your ROAS looks fine but the month-end balance keeps shrinking, the break-even calculation above is exactly what I work through in the first ten minutes of a diagnostic. Book a 20-minute call at https://calendly.com/pirohovmarketing/new-meeting and send me your site beforehand. I spend those 20 minutes on it and tell you the one thing I would fix first. If it makes sense to go deeper, there is a paid diagnostic after that.

Frequently asked questions

What is a good ROAS for ecommerce?
There is no universal answer because the right ROAS depends entirely on your margin after COGS, fulfillment, fees, and overhead. A 3x ROAS can be profitable for a high-margin product and catastrophic for a low-margin one. Calculate your break-even ROAS first, then set your target above it.

Why is my ROAS high but profit low?
ROAS only measures revenue returned per dollar of ad spend. It ignores every other cost in the business. If your combined COGS, shipping, fees, and overhead consume more of your revenue than your ROAS accounts for, you can run a technically strong campaign and still lose money on every order.

How do I calculate break-even ROAS?
Subtract COGS, shipping, fees, and any other variable costs from revenue, then divide by revenue to get your true pre-ad margin. Divide 1 by that margin percentage. The result is the minimum ROAS your campaigns must hit before the business makes any contribution toward fixed costs and profit.