Negative keywords: the control you do keep

In short: negative keywords tell Google which searches you do not want to appear for, even if they match your keywords. They are the counterweight to ever more elastic match types and, in practice, the fastest lever to stop wasting money. Careful: negatives have their own match types and behave differently from positive keywords.

If match types have become elastic, negatives are the elastic pulling the other way: they tell Google which searches you do not want to appear on even when they match your keywords. They are the most important control tool in a Search campaign, and the most neglected.

What is a negative keyword and how does it work?

A negative is a word or phrase that, if it appears in the search, stops your ad from being triggered. Example: you bid on "kitchen tap"; you add the negative free. The search «free kitchen tap» no longer triggers you.

The essential point, and what makes it different from ordinary keywords: negatives are (almost) literal. They do not expand by meaning. The negative cheap does not block «budget». For a while now Google does ignore capitals, accents and some obvious plural/singular pairs in negatives, but not synonyms: you have to add every form you want to block.

How do match types work for negatives?

Same symbols, different (literal) logic:

For 90% of cases, the single-word broad negative is what you want: free, jobs, course, second hand, pdf.

Where do negatives go: account, campaign or ad group?

1. Shared list (account level): negatives that apply to every campaign (the universal ones below). You create them under Tools → Shared library → Negative keyword lists and apply them to whichever campaigns you want. One list, many campaigns: change one word and it applies everywhere.
2. Campaign: negatives specific to that campaign. The classic use: in the generic campaign, add your brand as a negative (so those searches go to the brand campaign) and vice versa.
3. Ad group: to steer traffic to the right group (adding «price» as a negative in the Emergencies group so the search goes to the Quotes group).

Which negatives should you add from day one?

Almost every business selling something wants to block these intents from day one (adapt it to your case — if you sell courses, do not add "course" as a negative):

• Free / non-buyer: free, freebie, gift, download, pdf, manual, tutorial, template.
• Jobs: jobs, job, work, vacancies, salary, wage, apprenticeship, internship, cv, indeed.
• Training (if it is not your line of work): course, courses, training, masters, academy, syllabus, civil service exams.
• Pure information: what is, definition, wikipedia, meaning, history, examples.
• Second hand / used: second hand, used, preowned, ebay, gumtree, rental (if you sell).
• Do it yourself (if you sell a service): how to make, diy, homemade, step by step, youtube.
• Brands you do not sell and competitors (a strategic decision: sometimes it is worth bidding on them).

Thirty or forty well-chosen words prevent thousands of bad clicks.

Which negative-keyword mistakes block good traffic?

• Adding a negative for a word that is also in your keywords. The negative always wins: if you bid on «cheap tap» and add cheap as a negative, that keyword dies. Google flags a conflict, but you do not always look at it.
• Negatives that are too generic: price looks bad (informational) and is usually good (comparison ahead of a purchase). women, men and online should almost never be negatives in an ecommerce account.
• Adding a negative because of one expensive click. A term with one click and no conversion is not data, it is noise. Add negatives for patterns (roots that keep repeating), not for one-offs.
• Forgetting word order in phrase: "tap free" does not block «free tap». Use a single-word broad negative unless you need the precision.

💡 Ninja trick: negatives are the perfect example of a task a script does better than a person: clear rules, high volume, weekly repetition. Negative Keywords (White List) inverts the logic — you define what you DO want and everything else becomes a negative — and the Search Query Optimizer applies scenarios (spend with no conversions, low CTR, semantic irrelevance) to your real search terms. Both respect a rule you should follow by hand too: never add a negative for something that has converted.

What you should remember

• Negatives are literal: you have to add every form (no synonyms).
• Three levels: shared list (universals), campaign (brand/generic), ad group (steering traffic).
• Start with the universal list and grow it from the search terms report.
• Watch out for conflicts and for adding negatives on words that sell («price»).