How much should a DTC brand spend on ads?
As much as your unit economics can fund, and not a euro more. For a performance DTC brand, ad budget is an output: contribution margin sets your breakeven CPA, the profit you want per order sets your target ROAS, and the number of orders your funnel can find at that efficiency sets the spend.
TL;DR
- Percent-of-revenue budgeting is backwards for performance brands: budget is an output of margin math, not an input you pick in January.
- Four steps: contribution margin, breakeven CPA, target ROAS, affordable spend. Each is arithmetic, not opinion.
- Launching something new? Invert it: profit goal in, required spend and orders per day out, before any money moves.
- Every creative concept needs a minimum test budget. We size it as a multiple of breakeven CPA, not a round number.
- Budget increases are gated, not scheduled: efficiency, payback, creative supply, and inventory all clear first.
- The calculator embedded mid-article runs the whole model on your numbers, free, in the browser.
Why the percent-of-revenue rule is backwards
Ask how much to spend on ads and someone will quote you a percent of revenue. Ten percent if they are cautious, twenty if they feel aggressive. The rule survives because it comes from a world where it works: brand advertisers with annual calendars, spending against revenue that arrives whether or not the campaign runs.
A performance DTC brand lives in the opposite world. The ads create the revenue. That makes percent-of-revenue circular: percent of which revenue? Last month's, which last month's budget produced? The forecast, which depends on the budget you are setting? The rule asks the answer to define the question.
It also fails in both directions. Above target, a revenue cap starves the winner exactly when it should be fed. Below breakeven, "there is still budget left" keeps a loser alive until the quarter closes. Neither failure shows up in the percentage. Both show up in the bank account.
The fix is a change of direction: derive what one order can afford, then multiply by how many orders exist at that price. Margin first, volume second, budget last.
The budget framework: margin first, spend last
Four numbers, in order. Each falls out of the one before it.
Contribution margin = what one delivered order leaves after VAT and variable costs
Breakeven CPA = contribution margin (max ad cost per order at zero profit)
Target ROAS before fixed costs = AOV / (contribution margin - profit kept per order)
Affordable spend = allowable CPA x orders the funnel can find at that CPA
Take the same €40 store we walked through in the breakeven ROAS article: €40 AOV at 20% VAT, €8 landed product cost, €5.50 fulfillment, payment and COD fees, packaging, and a 6% rejection rate at €7 round-trip courier cost per refusal. After all of it, one placed order carries €17.19 of real margin. That number is your breakeven CPA, the spine of the budget: pay more than €17.19 for an order and you are buying losses. Divide it into the €40 AOV and you get the 2.33x breakeven ROAS your dashboard has to beat.
Breakeven is the floor, not the plan. The budget question starts one step later: how much of that €17.19 do you keep, and how much may the ad account spend? The first ladder uses a margin after ads, before monthly fixed costs, as a percentage of gross placed-order value including VAT.
| Margin before fixed costs | Kept per order for overhead and profit | Allowable CPA | Target ROAS |
|---|---|---|---|
| 0% (breakeven) | €0.00 | €17.19 | 2.33x |
| 10% | €4.00 | €13.19 | 3.03x |
| 15% | €6.00 | €11.19 | 3.57x |
| 20% | €8.00 | €9.19 | 4.35x |
At a 15% margin before fixed costs, every order may cost €11.19 in ads. Multiply that by the orders your funnel can find at that CPA: 800 orders allow roughly €9,000, and 2,000 allow about €22,400. The retained €6 per order still has to cover overhead.
To keep 15% net after €1,500 monthly fixed costs at €10,000 ad spend, the allowable CPA falls to about €9.73 and required ROAS rises to 4.11x. The calculator's margin planner includes this adjustment: target ROAS = (1 + fixed costs / ad spend) / (contribution per order / AOV - target margin). Its net margin percentage uses gross placed-order value, including VAT. Set a monthly budget before comparing its result with the ladder above.

Run your own store through it before reading on: the second half of this article assumes you know your number.



