Breakeven ROAS is the minimum return on ad spend you need to cover the cost of the goods or services you sell. If your campaigns are running below it, every sale you make through Google Ads is losing you money, even if the revenue numbers look healthy. We show you how to calculate it, how to use it to set targets your campaigns can actually hit, and what to do if you’re currently on the wrong side of the line.
Why Are Most Google Ads Accounts Optimising for the Wrong Number?
The default metric in Google Ads is ROAS, expressed as a multiple or percentage. Google’s Smart Bidding will happily optimise toward a target you set, but if that target isn’t grounded in your actual margins, you can hit it consistently and still lose money on every order.
A business sets a target ROAS of 4x because it sounds ambitious, or because a previous agency recommended it, without ever checking whether 4x is above or below their breakeven point. For a business with 30% gross margins, 4x ROAS is unprofitable.
For a business with 60% margins, it might be leaving significant growth on the table.
How to Calculate Your Breakeven ROAS
The formula is straightforward.
Breakeven ROAS = 1 / Gross Margin
Where gross margin is expressed as a decimal.
So if your gross margin is 40%, your breakeven ROAS is:
1 / 0.40 = 2.5x (or 250%)
At 2.5x, your ad spend is offset by gross profit. You’re not losing money, but you’re not making any either. Your actual target ROAS should sit above this number to leave room for operating costs and profit.
Worked example
| Metric | Figure |
|---|---|
| Average order value (AOV) | £200 |
| Cost of goods sold | £120 |
| Gross profit per order | £80 |
| Gross margin | 40% |
| Breakeven ROAS | 2.5x |
| Ad spend per order to break even | £80 |
| Sensible target ROAS (leaving ~50% profit margin on ad-driven revenue) | 5x |
If you’re an e-commerce business with this profile and your campaigns are running at 3x ROAS, you may think you’re doing well. You’re not. You’re losing £40 in gross profit per order once ad spend is factored in.
Does This Formula Work for Lead Generation Too?
Yes, with one extra step. Lead generation businesses don’t have a direct order value in their ad account, so you need to build the chain manually.
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Get Your Free Growth Plan →1. Work out your average customer lifetime value (LTV) or average contract value.
2. Apply your close rate to get average revenue per lead.
3. Apply your gross margin to get gross profit per lead.
4. That gross profit figure is your maximum allowable cost per lead (CPL).
Example:
- Average contract value: £3,000
- Gross margin: 50% = £1,500 gross profit per customer
- Close rate on qualified leads: 20%
- Gross profit per lead: £1,500 x 0.20 = £300
- Maximum CPL to break even: £300
If your Google Ads campaigns are delivering leads at £400 CPL, you’re losing £100 of gross profit per lead acquired. If they’re delivering at £150 CPL, you have real room to scale.
What Variables Change Your Breakeven ROAS?
Three things move the number.
1. Gross margin
This is the biggest lever. A software business with 80% margins has a breakeven ROAS of just 1.25x, meaning almost any positive return covers costs. A trade business with 20% margins needs 5x just to break even. Know your number before you touch bidding settings.
2. Return and refund rates
If 15% of orders are returned, your effective gross margin drops. Factor this in, especially for e-commerce. A 40% margin business with a 15% return rate has an effective margin closer to 34%, pushing breakeven ROAS up to roughly 2.9x.
3. Attribution model
Last-click attribution in Google Ads frequently over-credits paid search. If your account uses last-click and your actual customer journey involves multiple touchpoints, the ROAS your account reports is probably higher than the true contribution of paid ads. Data-driven attribution or a proper multi-touch model will give you a more honest figure to work with.
What to Do If Your Campaigns Are Below Breakeven ROAS
Running below breakeven is not automatically a signal to turn campaigns off. Diagnose before acting.
Step 1: Confirm the margin figure is correct
It sounds obvious, but many businesses use revenue as the denominator in their ROAS calculation without accounting for returns, fulfilment, payment processing fees, and VAT. Strip those out and recalculate.
Step 2: Segment by campaign and product
Aggregate ROAS hides everything. A single underperforming campaign or a low-margin product category can drag an account below breakeven while other campaigns are performing well. Pull performance data by campaign, ad group, product before making changes.
Step 3: Check for attribution gaps
If conversions are being tracked via the Google Ads tag only, without GA4 or CRM data to cross-reference, you may be under-reporting conversions and therefore under-reporting ROAS. Run a quick audit: compare Google Ads conversion volume against actual orders or leads in your backend system for the same period.
Step 4: Identify the cost driver
Below-breakeven ROAS has one of three causes:
- Cost per click is too high relative to conversion rate (often a Quality Score or match type problem)
- Conversion rate on the landing page is too low (a creative or offer problem)
- The margin data you’re using is wrong
Fix accordingly: reduce bid on broad terms, improve landing page conversion, or correct margin data. Mixing them up is how accounts spend three months on A/B testing landing pages when the real issue is broad match keywords burning budget on irrelevant traffic.
Step 5: Set a hard floor and a scale target
Once you have your breakeven ROAS, set two numbers in your account strategy document.
- Floor ROAS: Your breakeven figure. Pause or review after two consecutive weeks below this floor.
- Scale ROAS: The ROAS at which you’re comfortable increasing budget. This is typically breakeven ROAS plus a margin that reflects your overhead recovery and profit goals.
For the 40% margin business above, that might look like: floor at 2.5x, scale at 5x.
How to Set a Target ROAS in Google Ads That’s Actually Grounded
When you switch a campaign to Target ROAS bidding, Google will ask for a target. Most people enter a number that feels right. Here is how to do it properly.
1. Calculate your breakeven ROAS using the formula above.
2. Add a profit buffer. If you want to generate 20p of gross profit for every £1 of ad spend beyond breakeven, factor that in.
3. Look at your campaign’s historical ROAS over the last 90 days. If it has never hit your target, Google’s algorithm will restrict impressions significantly trying to hit an unachievable number. Start at a target close to historical performance and increase it incrementally.
4. Allow at least two to four weeks of data before judging performance after any target change. Smart Bidding needs time to adjust.
A common mistake is setting a very high target ROAS to “stay safe” and then wondering why impression share collapses. If your target is too far above what the campaign can realistically achieve, you’ll starve it of traffic and conversions, which makes optimising even harder.
A Note on Blended ROAS vs. Campaign-Level ROAS
Some businesses look at blended ROAS, which is total revenue divided by total ad spend across all channels. Use for reporting. Don’t use for campaign decisions.
If your brand search campaigns run at 15x ROAS (because people were going to buy anyway) and your prospecting campaigns run at 1.8x, the blended figure might look fine while your acquisition activity is losing money consistently. Measure each campaign type against its own breakeven benchmark and be especially careful about letting brand campaign performance mask problems in prospecting or non-brand activity.
FAQ
What is a good ROAS for Google Ads in the UK?
Good ROAS depends entirely on your gross margins. For a business with 40% margins, 2.5x is breakeven and 5x is healthy. For a business with 20% margins, you need 5x just to cover cost of goods, before operating expenses.
How do I find my gross margin for this calculation?
Gross margin is revenue minus cost of goods sold, divided by revenue. If you sell a product for £100 and it costs you £60 to produce or purchase, your gross margin is 40%. Check your accountant or management accounts. Use gross margin only; net margin will produce unachievable targets.
Should I use ROAS or CPA as my primary metric?
For e-commerce with consistent AOV, ROAS is usually more useful because it accounts for order value variation. For lead generation or service businesses where order values vary significantly, CPA (cost per acquisition) combined with a maximum allowable CPL calculation is often more practical. Use whichever metric connects most directly to a number that means something in your P&L.
My Google Ads ROAS is above breakeven but the business isn’t profitable. Why?
ROAS only covers cost of goods. It does not account for overheads, staff, software, agency fees, or your own time. Breakeven ROAS tells you when ad spend is covered by gross profit. To actually make money, you need ROAS high enough that the gross profit covers all other costs too. Model full margins, not gross margins alone, to find your true profitability threshold.
How often should I review my breakeven ROAS figure?
At minimum, quarterly. If your supplier costs change, your product mix shifts, or you introduce a new service tier, recalculate it. Running campaigns against an outdated margin figure is one of the quieter ways Google Ads budgets get wasted.
