From ACoS to profitable growth: how to actually optimize Sponsored Products

ACoS (Advertising Cost of Sales) is the first metric most accounts look at for Sponsored Products on bol.com and Amazon. Makes sense — it’s simple to calculate and directly visible in every advertising dashboard. But if you optimize purely for a low ACoS, you’re often optimizing for the wrong goal.

The problem with “low ACoS” as the only target

A campaign with a very low ACoS sometimes generates little extra revenue, because budgets and bids are set so conservatively that you leave opportunities on the table. Conversely, a slightly higher ACoS can come with significantly more revenue and, after accounting for margin, more profit overall. The question isn’t “how low can the ACoS go,” but “what ACoS maximizes total profitability, given my margin.”

What to look at instead

• Margin per product. An ACoS of 25% is perfectly sustainable for a high-margin product, but not for one with thin margins. Without margin visibility, any ACoS discussion is essentially meaningless.
• Incremental revenue, not just attributed revenue. Some of the revenue attributed to ads would have sold anyway through organic traffic. This effect is larger than often assumed, especially for strong, well-known products.
• Where the product sits in its lifecycle. A newly launched product often needs a higher ACoS to build visibility and reviews. An established product with a strong organic position can run with a lower share of ad-driven revenue.
• Keyword and placement level, not just campaign level. Campaign-level averages often hide the fact that a small number of keywords or placements are consuming most of the budget without return.

The practical approach

Profitable advertising growth doesn’t come from adjusting bids once — it comes from consistently looking at the combination of margin, ACoS per product group, and the stage a product is in, and applying a different steering model per segment instead of a single ACoS target for the whole account.