Break-even ad spend: how much can you pay for an order?
Calculate an acquisition ceiling before you buy traffic.
Find contribution before advertising
Subtract product cost, labor, net shipping and transaction fees from revenue. This amount is the maximum advertising cost the order can absorb before its contribution reaches zero. It is a ceiling, not a recommended budget.
A concrete example
For a $45 order with $12 product cost, $5 shipping, $6 labor and $1.65 fees, contribution before ads is $20.35. Paying $20.35 to acquire that order leaves nothing for overhead or profit. Paying $4 leaves $16.35 before overhead and income tax.
Convert the ceiling into ROAS
Return on ad spend is attributed revenue divided by ad spend. In the example, break-even ROAS is $45 ÷ $20.35, approximately 2.21. This only covers the included variable costs. If contribution before advertising is zero or negative, no positive acquisition spend is affordable under these assumptions.
Leave room for the rest of the business
Choose a target profit and an allowance for overhead and returns. Subtract these from your pre-ad contribution to set a more conservative acquisition ceiling. Do not assume repeat purchases will rescue an unprofitable first order without evidence.
Measure with care
Use the same time window and attribution basis for ad spend and orders. Platform-reported sales may overlap, include returning buyers or omit refunds. Start with a budget you can afford to lose and evaluate actual contribution, not just clicks or revenue.
Try it with your own numbers.
The free calculator includes labor, fees, shipping and ad spend.
Open the pricing calculator →Original worked examples by Margin Lab, prepared with AI assistance. Educational estimates; verify your own costs and provider terms.