Negative keywords are among the most important and most neglected parts of a Google Ads account. They tell Google which search queries should not trigger your ads, so you stop paying for clicks that never had a chance of converting. A well-maintained negative keyword list can cut wasted spend and lower your cost per acquisition (CPA) without touching bids or budgets. This guide explains how to build the list and keep it useful over time.
What Negative Keywords Do
When someone searches on Google, your ad becomes eligible to show if the query matches a keyword in your campaign. Negative keywords work in reverse by excluding queries that contain particular terms. If you sell premium running shoes and add “cheap” as a negative keyword, your ads stop showing for searches such as “cheap running shoes”, which saves the cost of clicks from people whose intent does not match your offer.
Negatives can be set at three levels: the campaign (applies to every ad group in it), the ad group (applies to one ad group) and shared negative keyword lists (apply to several campaigns at once). Campaign-level negatives are the usual starting point, and shared lists suit larger accounts.
One detail catches many advertisers out. Negative keywords do not expand to close variants the way positive keywords do. A negative for “job” will not automatically block “jobs” or a misspelling, so add the variants you want blocked.
Starting List: Categories to Exclude From Day One
Before campaigns go live, add negatives for the most predictable wasted-spend categories:
- Job and career terms: jobs, careers, salary, vacancy, apprenticeship.
- Research terms: what is, definition, examples of (unless you want informational traffic).
- Competitor brand names (unless you run a deliberate competitor strategy).
- Free and DIY terms: free, DIY, template, download (unless they match your offer).
- Review and comparison terms if your goal is direct sales instead of early research.
This list prevents the most obvious waste. The real work comes from reviewing what your ads actually matched.
How to Build Your List from the Search Terms Report
The search terms report shows the actual queries that triggered your ads and produced clicks. It is the best source of negative keyword ideas, so review it weekly for active campaigns and look for patterns. Our walkthrough on how to read a Google Ads search terms report shows what to look for.
When you find a poor query, ask whether the problem is the query or the match type. A broad match keyword such as “marketing software” may trigger searches like “free marketing software templates”. That points to either a negative for “free” or a tighter match type on the root keyword. Negative keywords and match types work together, and our guide to broad, phrase and exact match in 2026 explains how to choose.
The same report also surfaces good queries you had not targeted, so it feeds your positive keyword list as well as your negatives. Well-matched keywords help Quality Score too, which can lower what you pay per click. When you restructure campaigns around what you find, our guide to Google Ads campaign structure for e-commerce shows how to organise it.
Organising Negatives for Scale
As an account grows, campaign-level negatives become harder to manage. Shared negative keyword lists, found under the shared library in Google Ads, let you apply one list across many campaigns. They suit account-wide exclusions such as competitor names, job terms and research queries that you never want to show for.
A practical set of lists to maintain:
- Global exclusions: brand names, job terms, free and download terms, and other permanent exclusions for every campaign.
- Category exclusions: terms that are irrelevant to specific product lines or services.
- Match type protection: if you run broad match, a tighter set of phrase and exact negatives to stop those keywords reaching irrelevant or competitor queries.
How Often to Review Your Negative Keyword List
Review the search terms report weekly for the first month of a new campaign and at least monthly for established ones. Review it again within a week after major changes such as new keywords, a move to broad match or a bidding strategy change, because these often open up new irrelevant traffic.
Neglected negative keyword management is a common sign of an under-managed account, and it is also one of the quickest wins when you take over one. An hour spent in the search terms report of a mature account often turns up spend that can be redirected. It is one of several ways to lower your Google Ads cost per click and cost per acquisition without losing results. For the full maintenance routine, see our guide to setting up a Google Ads account the right way.
Frequently Asked Questions
How many negative keywords should an account have?
There is no target number. The list should grow with what your search terms report shows, and shared lists keep it manageable as it gets longer.
Which negative match type should I use?
Phrase and exact negatives are more precise. Broad negatives block a query only when all the words appear in it, and they do not cover close variants, so add plurals and misspellings you care about.
Can negative keywords hurt performance?
Yes, when they are too broad. A word that looks irrelevant can appear in valuable queries, so check the search terms report before adding a short, common word as a negative.
Do negative keywords work in every campaign type?
Support differs by campaign type and changes over time, so check the current Google Ads documentation for the campaign type you run.
Want expert help with your Google Ads? See our Google Ads management service.