Let me describe a scene. You open Seller Central on a Tuesday morning. Coffee in hand. You pull up Search Term Reports. You find a keyword called "yoga pants for cats" that has spent $87 this month on your fitness apparel campaign — and converted exactly zero times. You stare at it. Then you stare into the middle distance. Then you close the tab and tell yourself you'll deal with it later.
You won't deal with it later. Nobody does. That's why Amazon negative keywords are simultaneously the most powerful and most underused lever in Amazon PPC — and why every brand we audit has dozens of obvious negatives missing from their account.
This is the post that fixes that. [Cracks knuckles.] Let's talk about what negative keywords actually are, the three types you need to use, how to find them, where to add them, and the mistakes that turn a powerful efficiency tool into a campaign-strangling weapon.
What Negative Keywords Are (and Why They Matter)
A negative keyword is a search term you explicitly tell Amazon not to match your ads against. The opposite of a regular keyword. Where a normal keyword says "show my ad when someone searches for this," a negative says "under no circumstances show my ad when someone searches for this."
If your product is a protein powder and someone searches for "protein powder for dogs," that click is wasted spend — that customer is not buying your human protein. Negative keywords stop those clicks from happening in the first place. Amazon's own documentation puts it plainly: negative keywords prevent your ads from showing for queries that are unlikely to convert.
Why does this matter? Because every irrelevant click you pay for has a triple cost: you spend money on the click, you lower your campaign's conversion rate (which hurts ad rank), and you teach Amazon's algorithm that your keyword matches loosely-related queries (which makes the problem worse). Adding a negative is the cheapest possible way to cut all three at once.
Most accounts can drop ACoS 10–20% just by adding the obvious negatives that have been sitting in their search term reports for months. We cover the full lower-ACoS playbook here — negatives are lever #2 for a reason.
The 3 Types You Need to Know
Amazon gives you three flavors of negative keyword. They sound similar. They are not similar. Using the wrong one is how you accidentally suffocate a campaign. [Puts on the serious hat for one minute.]
Negative Exact
Blocks only the exact phrase you specify — nothing more, nothing less. Use when one specific search term is wasting spend but related variants might still be valid.
Negative Phrase
Blocks any search term that contains the phrase you specify, in any word order, with any additional words around it. Use when you want to block a whole category of irrelevant searches.
Negative Product Targeting (Negative ASIN)
Blocks your ads from showing on specific competitor ASINs or product pages. Available for Sponsored Products and Sponsored Display. Use when a competitor's listing keeps stealing your clicks without converting.
How to Find Negative Keyword Candidates
The negative keyword goldmine is one tool you already have: the Search Term Report. Pull it from Seller Central → Advertising → Reports → Search Term Report, or from the Amazon Ads console. Pick a date range that covers 30–60 days of meaningful spend.
Then sort by spend, descending. You're looking for three patterns:
- High spend, zero conversions. The most obvious negative candidates. Anything that's spent more than $10–15 with no conversions in 30–60 days goes on the list.
- High spend, terrible ACoS. Even if it's converting, an ACoS 3× your target with no signs of improvement is worth negating from broader campaigns and isolating in an exact-match campaign where you can control the bid.
- Obviously irrelevant terms. Search terms whose words don't match your product at all. "Vegan" on a whey campaign. "Dog" on a human supplement. "Cheap" on a premium-positioned listing. You don't need 30 days of spend data — you can flag these on sight.
For brands managing serious spend, the Search Term Report can balloon to thousands of rows. Our free PPC analyzer surfaces the top candidates in 60 seconds, so you don't have to manually sort. Or do it the manual way. Either works. (One is faster. Just saying.)
Where to Add Them (Account · Campaign · Ad Group)
Amazon lets you apply negatives at three levels. Each one does a different job. Mixing them up is how brands end up with bloated negative lists that block legitimate traffic.
Negative keyword lists (account-wide, via Sponsored Display or shared lists)
For category-wide blocks you never want anywhere in your account. Examples: free, cheap, knockoff, a competitor's brand name you never want to show up against. Apply once, blocks everywhere.
Campaign-level negatives
For terms that are irrelevant to one campaign but might be relevant to another. Example: "women's" as a negative in your men's campaign — but you'd want women's variants to still trigger your women's campaign. Keep these isolated to the specific campaign.
Ad-group-level negatives
For surgical control within a specific ad group. Used when you want to prevent keyword cannibalization between two ad groups in the same campaign. Example: your "branded" ad group has the brand name as a negative in your "category" ad group, so branded traffic doesn't get matched there.
Account-level for terms that are toxic everywhere (free, cheap, competitor brands). Campaign-level for terms that are wrong for one strategy but valid for another. Ad-group-level for cannibalization control. Most accounts under-use account-level and over-use ad-group level — which leaves them missing the broad blocks while drowning in granular ones.
5 Common Mistakes (and the Fix)
When NOT to Add a Negative
Negative keywords are powerful, which means they're also easy to misuse. A few situations where the right answer is "leave it alone."
The term has converted at least once in the last 30 days. One conversion isn't proof of efficiency, but it is proof that the term can convert. Better move: leave it in the broad campaign, but if it's converting consistently, harvest it into a manual exact match campaign with a controlled bid. Don't negate. Promote.
The term has low spend but high relevance. Sometimes a search term has only generated $3 in clicks because it's obscure — but those clicks are buying customers. Look at relevance, not just spend volume. A $3-spend, 1-conversion keyword is a $3 customer-acquisition cost. That's good.
You're in launch phase and trying to discover keywords. Auto campaigns at launch are supposed to be inefficient — you're paying Amazon to tell you what keywords your product attracts. Aggressively negating during launch starves your discovery. Give it 60–90 days before you get aggressive with negatives on a new product.
The Quarterly Negative Refresh
Negative keyword lists drift. New queries appear. Some old negatives no longer make sense (you launched a new product, or a category-wide block now blocks valid traffic). A quarterly refresh keeps the list intentional.
That's the playbook. Negative keywords are not glamorous. They will not get you a podcast invite. But they will quietly cut 10–20% of your ACoS in 60 days if you actually use them — and if you stack them with the other levers in our how to lower ACoS guide and the systematic approach to reducing ad spend waste, you'll see 25–40% drops in the first quarter.
Now go pull that search term report. Yes, right now. The cat yoga pants are waiting.
FAQ
Amazon negative keywords are search terms you explicitly tell Amazon not to match your ads to. They're the opposite of regular keywords — instead of triggering an ad when a customer searches for them, they block your ad from showing. Used correctly, they stop wasted spend on irrelevant clicks and tighten ACoS dramatically.
Pull your Search Term Report from Seller Central or the Amazon Ads console. Sort by spend, descending. Any search term with significant spend (more than $5–10) and zero conversions in the last 30–60 days is a candidate for a negative. Also flag terms that are clearly irrelevant to your product — even if they've converted once, they probably won't again.
Negative exact blocks only the exact phrase you specify. Negative phrase blocks any search term containing that phrase in any order. Use negative exact when you want to surgically remove one specific bad term. Use negative phrase when you want to block a whole category of irrelevant searches (e.g., "free" to block every variant of "free [your product]").
Pull the search term report and add new negatives every 2 weeks for active accounts, and at minimum monthly. Negative keyword maintenance is the single highest-ROI recurring task in any Amazon ad account. Set a recurring calendar reminder and treat it like payroll.
Yes, if you're too aggressive. Adding negative phrase or negative exact for terms that occasionally convert can starve a campaign of valid traffic. The rule: require at least $10–15 of spend with zero conversions over 60 days before adding a negative. Don't react to single-week noise.
Campaign-level for surgical control (when a specific keyword is irrelevant to one campaign but valid in another). Negative keyword lists (account-level) for category-wide blocks like "free", "cheap", or competitor brand names you never want to show up against. Most accounts need both, applied in the right places.