What are negative keywords in Amazon PPC?
Negative keywords in Amazon PPC are terms you add to a campaign or ad group to prevent your ads from appearing when shoppers use those specific search phrases. They stop your budget being spent on clicks that are unlikely to convert, which lowers wasted spend and improves your ACoS over time. When a shopper searches on Amazon, the platform checks whether their query matches any of your active keyword targets. Negative keywords work as an exclusion layer: before your ad enters an auction, Amazon checks whether the search contains any of your negative terms. If it does, your ad is excluded from that auction entirely, regardless of your bid. Amazon offers two negative match types for Sponsored Products campaigns. Negative exact match blocks only the precise phrase as entered, with no additional words. Negative phrase match blocks any search that contains your negative term as a substring, even if surrounded by other words. Negative phrase match is more powerful but needs to be used carefully: a negative phrase that is too broad can accidentally block converting searches that contain the same string. Every click on a non-converting search term is spend without a corresponding sale. That spend is included in your ACoS calculation. If 30% of your clicks come from search terms that almost never convert, that 30% of spend is contributing to your ACoS numerator while producing very little to your sales denominator. Removing those clicks by adding negatives reduces the numerator without reducing sales, which pulls ACoS down. The relationship is direct: the percentage of your spend that goes to non-converting search terms is roughly the percentage improvement in ACoS you can expect from negating them. A campaign spending 25% of its budget on zero-converting searches can achieve approximately a 25% ACoS reduction through systematic negative keyword management, without changing a single bid. Three categories of search terms produce the clearest candidates for early negation. The first is competitor brand names: if your broad or phrase match campaigns are triggering your ads when shoppers search for a specific competing brand you do not want to target, add those brand names as negative phrases. The second is research-intent queries: searches containing words like 'how to', 'what is', 'best', 'review', 'vs' and 'comparison' are usually browsing rather than buying searches, and they rarely convert for physical products. The third category is unrelated product types. Broad match keywords often generate impressions for tangentially related categories that have nothing to do with your specific product. A campaign for running trainers may trigger on searches for cycling shoes or football boots because the broad-match algorithm finds superficial similarity. Adding those unrelated product types as negative phrases prevents ongoing wasted spend on shoppers whose intent is entirely different from what your product addresses. Amazon allows you to add negative keywords at two levels: campaign level and ad group level. Campaign-level negatives apply across every ad group within that campaign. Ad group-level negatives apply only to the specific ad group where they are added. Use campaign-level negatives for terms you are certain should never trigger any of your ads in that campaign: competitor brand names and entirely unrelated product categories are good examples. Use ad group-level negatives when different ad groups in the same campaign target different audiences or product variants and the exclusion only makes sense for one of them. This prevents a negative keyword intended for one targeting set from inadvertently blocking a term that was performing well in a different ad group.
Negative keywords stop your Amazon ads from showing for irrelevant searches. Learn how to add them and which terms to block first.