ACoS (Advertising Cost of Sales)

ACoS is the most-cited metric in Amazon PPC management. It measures direct ROI on ad spend at the campaign, ad-group, or keyword level. ACoS does not include organic sales lifted by ad-driven traffic — that's TACoS (Total ACoS). For most private-label sellers, target ACoS depends on gross margin: if your blended margin is 30%, your break-even ACoS is 30%, so a profitable ACoS sits below that. New launches frequently accept elevated ACoS (sometimes 60-100%) for the first 14-30 days to push CVR-14 and review velocity, both of which feed organic rank under the post-May-2026 A10 weighting.