What ACoS is: the ad cost of sales on marketplaces

Anyone selling on marketplaces (Amazon, Wildberries, Ozon and others) quickly meets the metric ACoS — the advertising cost of sales (in the Russian market it's known as ДРР). It's the main indicator of ad effectiveness on a platform. Let's break it down.

What it is

ACoS shows what share of revenue went on advertising.

ACoS = ad spend ÷ revenue from ads × 100%

Example: ads cost $150 and brought $1,500 in sales → ACoS = 10%.

ACoS is "inverted" ROAS

• ROAS = revenue ÷ spend (higher is better).
• ACoS = spend ÷ revenue (lower is better).

ACoS 10% ≈ ROAS 10. Just two views of the same thing.

What counts as a normal ACoS

It depends on the product's margin. The key benchmark is the break-even point: ACoS shouldn't exceed your margin, or ads eat the profit. A high-margin product can bear a higher ACoS, a low-margin one can't.

How to lower ACoS

• The product card — good photos, description and reviews raise the impression-to-purchase conversion (a cheaper sale).
• Relevant queries — advertise on precise keywords, not "everything at once."
• Bids and bidding strategies — managing the cost per click.
• Organic — growing organic sales reduces dependence on paid ads.
• External traffic — seeding and creators bring cheap traffic to the card.

An important caveat

ACoS measures only on-platform advertising. Calculate profitability accounting for marketplace fees, logistics and COGS — a low ACoS still isn't a guarantee of profit.

Takeaway

ACoS is the share of revenue eaten by advertising; keep it below your margin. It's lowered through a strong card, precise queries and external traffic. We help bring cheap external traffic to your cards and reduce reliance on on-platform ads.