Advertising Cost of Sales (ACoS)

ACoS (Advertising Cost of Sales) is the percentage of ad-attributed revenue spent on advertising, used primarily on Amazon Ads. It's the inverse of ROAS.

FormulaACoS = (Ad spend ÷ Ad revenue) × 100%

Example

Spend $200 to drive $1,000 in ad sales → ACoS = (200 ÷ 1,000) × 100 = 20%. (That's the same as a 5x ROAS.)

Why it matters

ACoS is the standard efficiency metric for Amazon sellers. A lower ACoS is more efficient; your break-even ACoS equals your profit margin before ad spend.

Put these metrics to work

AdPlus plans, launches, and optimizes campaigns across 12 ad networks from one screen — and tracks every metric here for you. Free to start, no card.

Start free →

FAQ

What is a good ACoS?
A good ACoS is below your profit margin so ads stay profitable — often 15–30% for many sellers, but it depends entirely on your margins and goals (launch vs. profit).
What's the difference between ACoS and TACoS?
ACoS uses only ad-attributed sales; TACoS (Total ACoS) divides ad spend by total sales, showing how reliant your whole business is on ads.

Related terms