A 3× ROAS feels safe. On the store below, it works out to $715 of profit on $9,000 in sales, and adding $2,000 of ad spend turns that into a loss. A ROAS target copied from Twitter is about the most expensive number in e-commerce, and the fix takes one formula.
My view: every Shopify store running paid traffic should know three numbers by heart: break-even CPA, break-even ROAS per order, and break-even ROAS once fixed costs are included. The third is the one almost nobody calculates, and it’s the one that decides whether the month is profitable.
The break-even ROAS calculator works all three out from your costs. Here’s what it’s doing and how I’d use the results.
Step 1: contribution margin per order
Say a store sells a $60 average order:
- Product cost $22, shipping and fulfilment $6, packaging $1
- Payment fee (Basic + Shopify Payments): 2.9% × $60 + $0.30 = $2.04
- Returns allowance at 3%: $1.80
- Contribution margin: $27.16 per order (45.3%)
Most online break-even formulas stop at price minus product cost, which would give $38 here. That overstates it by about 40% because it ignores fees, shipping and returns.
Step 2: the three break-even numbers
- Break-even CPA = $27.16. If you pay more than that to win a purchase, that order loses money.
- Break-even ROAS per order = $60 ÷ $27.16 = 2.21×. This covers each order’s own costs.
- Break-even ROAS with fixed costs = 2.47×. Add $3,000 of ads and $359 of fixed costs (plan $39, apps $120, other $200). You then need 124 orders (about $7,420) a month to break even.
At 2.21× the store covers each order but not the plan, the apps or anything else. The number to use as your account-level target is 2.47×.
Step 3: where the store actually is
At 150 orders on $3,000 of ads, the store has $9,000 in revenue, a 3.0× ROAS, a $20 CPA and $715 a month in profit. It’s profitable, but only just. The cushion is $7.16 per order under break-even CPA.
The scaling trap
Raise ads to $5,000 and keep everything else the same:
- If orders stay at 150, ROAS falls to 1.8× and the month loses $1,285.
- If the extra spend lifts orders to 200, ROAS is 2.4× and profit is $73, down from $715.
More budget nearly always raises CPA. Break-even CPA stays exactly where it was. So scale only from headroom you can measure.
What moves break-even (one change at a time)
| Change | Break-even ROAS | Profit at 150 orders |
|---|---|---|
| Baseline | 2.21× | $715 |
| Third-party gateway on Basic (+2%) | 2.31× | $535 |
| Returns 8% instead of 3% | 2.48× | $265 |
| COGS $18 instead of $22 | 1.93× | $1,315 |
| Customer pays shipping | 1.81× | $1,615 |
| AOV $75 instead of $60 | 1.82× | $2,832 |
Margin levers outweigh ad tweaks. A $15 AOV lift roughly quadruples profit, which no creative test will do. And the Grow plan doesn’t help yet: at $9,000 a month, the lower card rate is outweighed by the higher plan fee (profit falls to $667).
What I’d do
- Calculate break-even from real costs: landed COGS, your actual pick-pack-and-postage, and your returns rate from the last 90 days. Supplier quotes and averages are too optimistic.
- Use break-even ROAS including fixed costs as your account floor. Any campaign that stays below it for a full learning window gets fixed or switched off. That rule applies regardless of what the dashboard says.
- Pull one margin lever before you raise budget. A bundle, a free-shipping threshold or a returns fix comes first. Scale spend only once current CPA sits well under break-even CPA.
For the per-order version of this without fixed costs, see Shopify profit margin after Facebook ads. To turn break-even into a conversion-rate target, see conversion rate needed to hit a profit goal.
Work with me
I’m Faraz, a Shopify and AI automation consultant. If your ROAS looks fine but cash doesn’t, I can work through your break-even numbers with you and pick the lever that pays first. farazhussain.com · WhatsApp +92 334 3454747.
All figures are an illustrative worked example using approximate 2026 US Shopify rates.