Negative Keywords: Stop Wasting Your Ad Spend
If your ACoS is stubbornly high, the culprit is usually not your bids — it's the searches you're paying for that were never going to buy. Negative keywords are how you tell Amazon to stop showing your ad on those terms. It's the least glamorous lever in PPC and quite possibly the most profitable. Here's how to use it properly.
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What negative keywords do
A negative keyword prevents your ad from appearing when a shopper's search contains that term. If you sell premium glass water bottles and keep getting clicks on "plastic water bottle" that never convert, adding "plastic" as a negative stops those clicks — and the spend — cold. You're not losing sales; you're refusing to pay for searches that were never a fit.
Every dollar you stop wasting on irrelevant clicks is a dollar you can redirect to the keywords that actually convert. Negatives don't just cut cost — they reallocate it.
Negative exact vs. negative phrase
Amazon gives you two negative match types, and choosing the right one matters.
| Match type | Blocks | Use when |
|---|---|---|
| Negative exact | Only that exact search term | A specific term wastes spend but close variants still convert |
| Negative phrase | Any search containing that phrase in order | A whole family of searches (e.g. anything with "for kids") is wrong for you |
Reach for negative phrase when you want to sweep out a category of searches, and negative exact when you want surgical precision without accidentally blocking profitable variations.
Mining your search-term report
The search-term report is where negatives come from. It shows the actual shopper queries that triggered your ads, along with clicks, spend, and sales for each. Your job is to find the terms that are spending without selling. A simple, repeatable process:
- Filter for search terms with clicks but zero orders.
- Set a spend threshold — for example, any term that has spent more than the price of your product without a single sale.
- Judge relevance: is this term genuinely off-target, or just under-tested? Only negate the clearly irrelevant ones.
- Add the wasteful terms as negatives at the right level and match type.
Quick tip
Don't negate too fast. A term with three clicks and no sale might just need more data. Give keywords enough clicks to be statistically meaningful before you cut them.
Where to place your negatives
Negatives can be added at either the campaign or the ad-group level, and the distinction matters. A campaign-level negative blocks the term across every ad group in that campaign, which is what you want for a term that's simply irrelevant to the whole product. An ad-group-level negative is more surgical — useful when a term converts in one ad group but wastes spend in another. As a rule, negate broadly irrelevant terms at the campaign level and use ad-group negatives to steer traffic between tightly themed groups.
Negatives as traffic sculpting
Negative keywords aren't only about cutting waste — they're also how you direct search terms to the right campaign. In the auto-to-manual flow, once a keyword proves itself and graduates into an exact-match campaign, you add it as a negative in the auto or broad campaign it came from. That stops the two campaigns from bidding against each other on the same term and ensures the search lands in the campaign where you've set the ideal bid. Used this way, negatives keep your whole account structure coherent.
How often to review
Negative-keyword work isn't a one-time cleanup; it's ongoing hygiene. New search terms surface constantly, especially from auto and broad campaigns, so a weekly or biweekly pass through the search-term report keeps waste from accumulating. Newer, higher-spend accounts benefit from more frequent reviews, while mature, well-pruned accounts can stretch the interval. The key is consistency — a small regular habit beats an occasional heroic cleanup.
Common negatives to catch early
- Competitor brand names that never convert for you.
- Wrong-attribute terms: "plastic" when you sell glass, "cheap" when you're premium.
- Wrong-audience terms: "for kids," "wholesale," "bulk" if that's not you.
- Freebie hunters: searches containing "free" or "sample."
Automating the hunt
Combing the search-term report by hand every week is tedious, and tedium is why most sellers stop doing it. Helium 10's Adtomic automates search-term mining: it flags wasteful terms against your rules and lets you add negatives in a couple of clicks, while also surfacing the winners worth promoting. It turns an hour of spreadsheet work into a quick review.
A caution against over-negating
It's possible to take negatives too far. Aggressively cutting every term that hasn't converted yet can starve your campaigns of the exploration that finds new winners, and overly broad negative phrases can accidentally block profitable searches you never intended to lose. Before adding a broad negative, think through what else it might catch — a negative phrase of "case" meant to block phone cases could also block a legitimate "travel case" search. Negatives are a scalpel, not a hatchet; used with a little restraint they cut waste without cutting into your growth.
The bottom line
Negative keywords are the cheapest optimization in Amazon PPC — no new creative, no bigger budget, just less waste. Build a weekly habit of mining your search-term report, cut the clearly irrelevant terms, and watch your ACoS fall while your sales hold steady.
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