How to find negative keywords in Google Ads

by Harry Watts · Last reviewed 14 October 2026

Find negative keywords in the search terms report, sorted by cost, and add each one at the match type and level that blocks only what you mean to block. A negative keyword is far more literal than a normal one: it doesn't stretch to plurals, synonyms or close variants, and it only works where you've applied it. That is why the ones you've already added can seem not to work.

The biggest offender I find in accounts is irrelevant searches with no systematic negative keyword structure behind them. It's the first leak in where Google Ads budgets leak, and this guide is the practice behind fixing it: where to look, what each type of negative actually blocks, why one you added is still letting ads through, and the negatives that do more harm than the searches they stop.

Where to find them: the search terms report

The search terms report shows the searches people actually typed before your ads appeared, as opposed to the keywords you chose. In Google Ads it's under Campaigns, then Insights and reports, then Search terms (Google's search terms report page).

Set the date range to the last 90 days, sort by cost with the most expensive first, and filter to searches with no conversions. Work down from the top. Going through the report alphabetically, or adding whatever catches your eye, spends your time on the cheap rows and leaves the expensive ones running.

The expensive ones are rarely obvious until you look. On a B2B account I've worked on in the past, roughly £70,000 went over a year or two on searches that were never going to become customers: Google had matched its keywords to consumer brand searches, people typing a well-known company's name to find its website. The real terms stay private, but the pattern is the same as a workplace catering company paying for "greggs opening times".

The report doesn't show everything. Google leaves out searches that don't have enough volume, to meet its privacy standards, and doesn't say where the line is, so some of what you paid for will never appear by name.

Before an account has any history, the same thinking works from the other side. Keyword Planner and Google's autocomplete show what else people type around your keywords, and the phone is a source too: if callers keep asking for a service you don't offer, someone is searching for it and finding you.

What each negative match type blocks

Negative keywords have the same three match types as normal ones, but they behave differently, and the difference is where most mistakes start. The rules below are Google's (about negative keywords), shown for a heating engineer who wants to stop paying for repair searches:

The column people miss is the last one. A normal keyword stretches to cover close variants; a negative doesn't. Google says you have to add synonyms and singular or plural versions yourself. It does handle capital letters and misspellings automatically.

Why a negative isn't working

When a client tells me they've added the negatives and the ads are still showing, I ask two things. First, which negative match type did they use? Second, where did they add them: at campaign level, ad group level, account level, or in a shared negative keyword list?

Those are the first two things to check. The rest are on Google's own troubleshooting list (troubleshoot negative keywords):

• It's a plural, synonym or close variant. A negative doesn't stretch the way a keyword does: [boiler repair] won't stop "boiler repairs". Add each version you want blocked.
• The match type is too narrow. An exact negative blocks one search. If "boiler repair near me" is still showing, the exact negative [boiler repair] was never going to stop it. Check the table above.
• It's at the wrong level. Google has you choose the campaign or ad group a negative applies to (adding negatives to campaigns). An ad group negative only covers that ad group, so the same search can still trigger an ad in the next one, and a campaign negative covers one campaign. A negative keyword list does nothing until it's applied to campaigns, and Google says lists "need to be associated with specific campaigns to be active". Account-level negatives, up to 1,000 of them, apply to Search and Shopping inventory across the account, Performance Max included.
• The search runs past 16 words. Google ignores a negative that comes after the sixteenth word. Rare, but it explains the odd stray.
• The date range is older than the negative. If you added it on Tuesday and you're looking at the last 30 days, the report still shows the clicks from before. Change history in Google Ads shows when it went in.
• It's a different campaign type. Negatives work differently on Display and Video. On Display, Google says a set of negatives is excluded as a topic rather than as a search. In Performance Max they only reach Search and Shopping inventory, which matters most for brand searches: that's covered in Performance Max explained.

The negatives that backfire

There's a story you'll hear in this industry. Someone means to exclude one word as an exact match negative, because that word typed on its own was bringing in a trickle of meaningless clicks. They add it as a broad match negative instead, and it tanks the account overnight.

To make that concrete (an illustration, not a real account): a plumber sees a few clicks from people searching just "plumbing". They mean to add [plumbing] as an exact negative. They add plumbing as a broad negative, and every search containing the word stops showing an ad, including "emergency plumbing near me", the search they pay for most.

I'm sure I have a few minor blunders on my record, but thankfully nothing too costly, and I want to keep it that way. I can't emphasise enough the importance of being extra careful and making sure you fully understand the context of the search terms, the keywords and the campaign. Especially now these tasks can be built into agentic AI workflows.

The same goes for the generic starter lists that most guides recommend. They're built for nobody's business in particular, and some of their favourite words are a service business's best searches:

• "Free". Sensible for blocking "free boiler manual". Disastrous for "free quote roofer", which is someone asking you for a price. For a local trade, block the free searches that are research, not the ones asking to be quoted.
• "Cheap". Someone searching "cheap emergency electrician" at 11pm still needs an electrician. Whether to block it is a pricing decision, not a housekeeping one.
• "Near me". It turns up in lists of words to watch. For a business that serves its local area, it's often the strongest signal in the search.

Before adding any one-word broad negative, test it. Filter the search terms report to searches containing that word over the last 90 days and look at what it would have blocked: the cost, the conversions, and every search you'd still want. If any of them converted, it's the wrong negative, or the wrong match type.

A routine that keeps it under control

Negatives work best as a structure rather than a pile. Shared lists let you build each family of bad searches once and apply it to every campaign that needs it. Google allows up to 20 lists per account and 5,000 negatives per list (negative keyword lists). A structure that suits most service businesses:

• Jobs and training. "Jobs", "salary", "apprentice", "course".
• Doing it themselves. "How to", "DIY", "manual", tested first in case a how-to search ever converts.
• Services you don't offer. The specific ones that keep turning up, which only your own report can tell you.
• Brand. Your own brand terms, for any campaign that shouldn't be paying for them, like Performance Max.

Wrong-area searches are usually better fixed with location targeting than with place names as negatives, which is a settings check rather than a list.

Then review the search terms report on a schedule, starting from the most expensive rows every time. A new account, or one leaning on broad match, turns up new waste quickly; a mature account with a good structure turns up less. When a review finds nothing that costs real money, stop adding. Google warns that with too many negatives your ads might reach fewer customers, and every negative you add is one more thing that can block a search you wanted.

Quick answers

If you'd rather not do it yourself

Going through the search terms report and the negative structure is part of every paid audit I do. If you'd like to talk it through first, a free intro call is thirty minutes.