What Is a Negative Keyword?
A negative keyword works as the opposite of a regular keyword. Where a regular keyword tells Google which searches should trigger your ad, a negative keyword tells Google which searches should not. When a user's query contains your negative keyword, your ad is suppressed entirely for that auction, preventing an irrelevant click and preserving your budget for searches that actually match your business.
Negative keywords are available in the same three match type formats as regular keywords. A negative broad match term excludes any query containing that word or a close variant. A negative phrase match term excludes queries that contain the phrase in that order. A negative exact match term only excludes queries that are an exact or very close match to the specified term. For most cases, negative broad match or negative phrase match are appropriate, as they provide broader protection without requiring you to anticipate every possible phrasing.
Negative keywords are one of the highest-impact, lowest-cost optimisations available in Google Ads. Because they reduce wasteful clicks without changing anything about your bids or targeting, the budget savings from negative keywords flow directly into more impressions and clicks on relevant searches. For South African businesses, where ad budgets are often modest and every rand of misplaced spend is felt, negative keyword maintenance is not optional but a fundamental management discipline.
Negative keyword lists are a related feature that allows you to create a shared list of negative keywords and apply it to multiple campaigns simultaneously. This is particularly useful for business categories with common irrelevant modifiers. A law firm, for instance, might create a negative keyword list containing terms like "free", "DIY", "template", "study", and "course" and apply it across all their campaigns to block query types that indicate research rather than purchasing intent.
Negative Keyword In Practice
A Johannesburg car dealership selling new and used cars runs a Google Ads campaign. Their primary keywords target queries like "buy used car Johannesburg" and "new Honda Johannesburg". Without negative keywords, their ads might show for "car hire Johannesburg", "car service Johannesburg", "car parts Johannesburg", and "driving lessons Johannesburg", all of which contain the word "car" and are geographically relevant but represent completely different buyer intents. Adding "hire", "service", "parts", and "lessons" as negative keywords immediately stops the bleeding of budget into these irrelevant categories.
The process for building a negative keyword list is straightforward but requires regular attention. Review the Search Term Report in Google Ads at least once per week, particularly in the first three months of a new campaign. Any query that received a click but was clearly not related to your business should be added as a negative keyword. Over time this process becomes less intensive as the most common irrelevant queries are already blocked. Many South African advertisers who inherit neglected accounts find significant cost savings within the first two weeks simply by reviewing the Search Term Report and adding the obvious negatives that previous managers had overlooked.
How negative keywords work, and the match types
A negative keyword stops your ad showing for searches containing that term. It is the primary tool for controlling what broad and phrase matching buys on your behalf.
| Negative match type | Blocks | Use for |
|---|---|---|
| Broad negative | Searches containing all the words, any order | General exclusions like free, jobs, DIY |
| Phrase negative | Searches containing the exact phrase in order | Specific unwanted combinations |
| Exact negative | Only that exact search | Surgical exclusions where close variants are wanted |
Note that negatives do not match close variants the way positive keywords do: block the plural and the misspelling explicitly if you need them blocked.
Building and maintaining the list
- Start before launch with the obvious categories: free, cheap, jobs, salary, DIY, course, template, and competitor brand names if you do not want that traffic.
- Mine the search terms report weekly for the first month, then monthly. This is where real waste is visible.
- Use shared negative lists across campaigns so an exclusion added once applies everywhere.
- Add negatives at the right level. Account level for universal exclusions, ad group level to steer traffic between your own ad groups.
- Review quarterly. An over-aggressive list eventually blocks searches you want.
In audited accounts, missing negatives is consistently one of the largest sources of wasted spend. See cutting wasted ad spend and our Google Ads management.
FAQ
Where should negative keywords be added, at campaign or ad group level?
Add negative keywords at campaign level when they are irrelevant to your entire campaign, such as competitor brand names you do not want to appear for. Add them at ad group level when a term is relevant to the campaign overall but should not trigger a specific ad group. Negative keyword lists shared across campaigns save time and ensure consistency.
How many negative keywords should a campaign have?
There is no fixed number. A well-managed campaign typically builds its negative keyword list continuously by reviewing the Search Term Report weekly and adding irrelevant terms as they appear. New campaigns for South African businesses often accumulate 50 to 200 negative keywords in the first three months, with the list growing more slowly as the campaign matures.
How many negative keywords should a campaign have?
There is no target number. What matters is that the search terms report shows no meaningful spend on irrelevant queries. New accounts typically add dozens in the first month, then a handful a month once the obvious waste is blocked.
Do negative keywords match close variants?
No. Unlike positive keywords, negatives do not automatically block plurals, misspellings or close variants. If you need those blocked, add them explicitly.