Break-Even ROAS: How to Calculate It (With Example)

Your break-even ROAS is the minimum return your ads need so you don't lose money on each sale. You get it by dividing revenue per order by the margin you keep before paying for ads. This guide gives you the formula, which costs to include (and the ones people usually forget), how VAT and sales tax affect the number, and an illustrative worked example you can copy with your own data.

What break-even ROAS is and why it matters more than a "good" ROAS

ROAS (return on ad spend) measures how much revenue each unit of currency spent on ads brings in. A ROAS of 3 means every €1 (or $1) spent generated €3 in sales.

The problem is that a ROAS of 3 means nothing on its own. For a store with healthy margins it can be very profitable; for another with an expensive product and costly shipping it can mean losing money on every order. That's why questions like "what's a good ROAS?" don't have a universal answer.

Break-even ROAS answers a far more useful question: at what ROAS do I stop losing money?

• Below that number, every sale attributed to ads costs you money.
• Right at that number, you cover your costs but make nothing.
• Above it, you start generating profit.

When someone asks "why aren't my ads converting?", the ad is often converting just fine, but the store is operating below its break-even point without realizing it.

The break-even ROAS formula

The clearest version is this:

Break-even ROAS = Revenue per order ÷ Contribution margin per order

Or, expressed as a percentage:

Break-even ROAS = 1 ÷ Contribution margin %

Here, contribution margin is what you keep from each order after paying all variable costs (product, shipping, fees, returns…), but before paying for advertising.

That gives you another equally important figure:

Maximum CPA = Contribution margin per order

In other words, the most you can pay to acquire a sale without losing money. Many sellers find CPA more intuitive to track than ROAS, and both tell you the same thing from different angles.

Step by step: calculate your contribution margin

This is where almost all mistakes happen. The usual error is subtracting only the product cost and forgetting everything else. Build the full list for your average order:

1. Selling price excluding VAT or sales tax. If you sell in a market where prices include VAT (for example, Spain at 21%), divide by 1.21 (or whatever rate applies to your product). That tax isn't yours: you collect it and pass it on to the tax authority.
2. Product cost (COGS). What you pay the supplier per unit, including customs duties or import costs if any.
3. Shipping to the customer. What it costs you, not what you charge. If you offer free shipping, it's a full cost.
4. Payment fees. Gateway, card fees, buy-now-pay-later… Check the current rates of your payment provider and your Shopify plan.
5. Packaging and handling. Boxes, filler, labels, warehouse or fulfillment costs.
6. Returns and refunds. Set aside a provision: if a share of orders gets returned, spread that cost across all orders.
7. Gifts, samples or discounts. If nearly every order uses a code, the discounted price is your real price.

Contribution margin = Price excluding tax − sum of variable costs (2 to 7)

Fixed costs (apps, theme, tools, salaries) don't go in here. We cover them further down, because they're what takes you from per-order break-even to real monthly profit.

Illustrative worked example

Illustrative example with made-up figures to explain the calculation. Replace them with your own.

Imagine a store selling a product at €39.90 including VAT (21%), with an average order of one unit.

With that:

• Maximum CPA: €15.83. If acquiring a customer costs more, you lose money.
• Break-even ROAS (on revenue excluding VAT): 32.98 ÷ 15.83 = 2.08.
• Break-even ROAS (on revenue including VAT): 39.90 ÷ 15.83 = 2.52.

Notice the gap between 2.08 and 2.52. That gap is exactly what makes many stores believe they're profitable when they aren't.

VAT, sales tax and how Meta and TikTok report revenue

The ROAS you see in Ads Manager is calculated from the conversion value your pixel or Conversions API sends. Depending on how the integration is set up, that value may include tax, shipping or discounts.

Before comparing numbers, check:

• What value your store sends as the "purchase value": subtotal, total including tax, with or without shipping. Review the settings of your sales channel or your Meta and TikTok integration, and compare a test order with what shows up in the event.
• Which currency it's reported in and whether it matches your ad account.
• Which attribution window you're using. A longer window usually attributes more sales to ads than a shorter one.

The practical rule: always compare apples to apples. If the platform reports revenue including tax, use your break-even ROAS calculated with tax (2.52 in the example). If it reports without tax, use the other one.

It's also worth tracking MER (marketing efficiency ratio): total store revenue ÷ total ad spend. It doesn't depend on each platform's attribution and protects you from Meta and TikTok both claiming the same sale.

From break-even to target ROAS: profit and fixed costs

Breaking even doesn't pay the bills. You need two more adjustments.

1. Add the profit you want per order

Target ROAS = Revenue per order ÷ (Contribution margin − Desired profit per order)

Continuing the illustrative example, if you want to make €5 net per order:

32.98 ÷ (15.83 − 5) = 32.98 ÷ 10.83 ≈ 3.05 (excluding VAT)

Your target CPA would drop to €10.83.

2. Spread your fixed costs

Apps, subscriptions, theme, email tools, accounting… You pay for all of it even when you don't sell. A simple way to include it:

1. Add up your monthly fixed costs.
2. Divide them by the number of orders you expect that month.
3. Subtract that amount from your contribution margin before calculating target ROAS.

Illustrative example: €300 in monthly fixed costs and 400 expected orders works out to €0.75 per order. The margin available for ads and profit drops from €15.83 to €15.08.

If you're not sure how much you pay for apps each month, the free Shopify store auditor detects the apps a store uses and estimates their monthly cost, which helps you fine-tune this part of the calculation.

How to lower your break-even ROAS

If your actual ROAS sits below break-even, you have two paths: improve the ads, or make your store need less ROAS to be profitable. The second is usually easier to control.

Increase average order value

Some costs (shipping, packaging, part of the payment fee) don't grow at the same pace as the order. That's why a bigger order usually leaves more margin proportionally.

Illustrative example: if a quantity discount gets the customer to buy 2 units for €69.90 including VAT:

• Price excluding VAT: €57.77
• Costs: product €18, shipping €4.50, payment fee €2.10, packaging €0.80, returns €2.89 → €28.29
• Contribution margin: €29.48
• Break-even ROAS excluding VAT: 57.77 ÷ 29.48 ≈ 1.96 (previously 2.08)
• Maximum CPA: €29.48 (previously €15.83)

Break-even ROAS drops only slightly, but the key point is that you nearly double what you can pay per customer, which gives you room to bid higher in competitive auctions.

The usual levers for raising order value are quantity breaks, complementary products, cart suggestions and a well-placed free-shipping threshold. On the Pixelion features page you can see how the theme builds in quantity breaks, upsells, a cart drawer with a free-shipping progress bar and a free-gift threshold without relying on extra apps, which also trims your fixed costs.

Improve unit margin

• Renegotiate with your supplier or buy in larger batches when volume allows.
• Review shipping: rates, box size, free-shipping threshold.
• Reduce returns with clearer product pages: size guides, real photos, visible delivery times.
• Adjust your price. Sometimes a small increase shifts your break-even point a lot without hurting conversion much. Test it carefully.

Factor in repeat customer value

If your customers come back to buy again, you can accept a ROAS close to break-even on the first purchase and profit on the following ones. But only do this with real repeat-purchase data from your own store, not assumptions. Without that history, the safe move is to require profitability from the first order.

Common mistakes when calculating break-even ROAS

• Treating the tax-inclusive price as revenue. It inflates your margin and artificially lowers break-even.
• Forgetting returns. In niches like fashion they can completely change the result.
• Calculating it once and never revisiting it. Change supplier, carrier or price, and your number changes.
• One ROAS for the whole store. If your products have very different margins, calculate break-even per product or per campaign.
• Relying only on platform-reported ROAS. Cross-check it against your actual Shopify sales and your MER.
• Judging a campaign after a few days. The first days are usually unstable; decide in advance how much spend and time you'll give it before making a call.

How to use it day to day with Meta and TikTok

Once you have your numbers, turn them into simple decision rules:

1. Write down three numbers per product: maximum CPA, break-even ROAS and target ROAS (with and without tax, depending on how your pixel reports).
2. Consistently below break-even: pause or change the creative, angle or audience.
3. Between break-even and target: keep it running and optimize (new hooks, a better product page, higher order value).
4. Consistently above target: scale the budget gradually and watch that CPA doesn't spike.
5. Review every month your MER and real profit in your books.

With this, you stop wondering whether a ROAS is "good" and start knowing exactly which campaigns make you money. If you're building or redesigning your store while launching ads, work on margin and average order value first: it's the most direct way to turn the same ad from losing money into making it.