If you run ads for a trade or service business and you only ever do one piece of maintenance on the account, make it this. Negative keywords are the list of things you refuse to pay for, and for most local businesses they are the difference between advertising being worthwhile and being a slow leak.
What a negative keyword actually does
When you add a keyword, you are telling Google what you want to appear for. When you add a negative keyword, you are telling it what to ignore. If you sell new bathroom installations and you add "diy" as a negative, your ads stop appearing for searches containing that word. You are not blocking customers. You are blocking people who were never going to buy from you.
They come in the same match types as normal keywords. Broad negatives block any search containing the word. Phrase negatives block searches containing the words in that order. Exact negatives block only that precise search. For most businesses, broad negatives are what you want, and you should be careful with them for exactly the same reason: they are powerful.
Why trade businesses need them more than most
Trade searches attract a lot of people who are not customers. Students and apprentices researching. Homeowners looking for instructions so they can avoid paying anyone. People looking for jobs. Other tradespeople checking prices. Suppliers. And the search terms they use sit right next to the ones your actual customers use, which is why Google mixes them up.
On top of that, your clicks are not cheap. Emergency and high-value trade keywords are among the more expensive things you can bid on, so every wasted click hurts more than it would for a low-value product.
A starting list
Treat this as a base to adapt, not gospel. Read every line and ask whether it applies to you, because one business owner's waste is another's best customer.
People who want to do it themselves
- diy
- how to
- tutorial
- step by step
- instructions
- youtube
- video
- guide
- fix it myself
People looking for work, not workmen
- jobs
- job
- vacancy
- vacancies
- hiring
- career
- careers
- apprentice
- apprenticeship
- salary
- wages
- how much do plumbers earn
- cv
- recruitment
Students and researchers
- course
- courses
- training
- qualification
- nvq
- college
- exam
- certification
- definition
- meaning
- wikipedia
Bargain hunters and freebie searches
- free
- cheap
- cheapest
- discount code
- voucher
- grant
- funding
- council
- second hand
- used
Trade suppliers and wholesale
- wholesale
- supplier
- suppliers
- trade counter
- parts
- spares
- tools
- screwfix
- toolstation
- wickes
- b&q
Other people's businesses
Add competitor names as negatives if you do not want to appear against them. Some businesses do want to, and that is a legitimate tactic, but it should be a decision rather than an accident. Also add the names of the big lead-generation sites and directories, because searches containing them are usually people trying to reach that platform.
Jobs you do not do
This is the most valuable section and the only one nobody can write for you. List every service people assume you offer and you do not. Commercial work if you are domestic only. Gas if you are not registered. Anything outside your radius. Every one of those becomes a negative keyword, and each one saves you money every month from now on.
Places you do not serve
If you cover one town and the next county keeps showing up in the search terms report, add those place names as negatives. Location targeting alone often does not stop this, because someone in your town can still search for a city two hundred miles away.
How to build your own list properly
The list above is a head start. The real list comes from your own search terms report, which shows what people typed before your ads appeared. Open it once a fortnight to begin with, sort by cost, and read the top rows. Anything that made you wince becomes a negative. After a couple of months, monthly is usually enough.
Keep your negatives in shared lists rather than adding them campaign by campaign. In Google Ads these live in the shared library, and it means one addition applies everywhere at once. It also means that when you launch a new campaign, you can attach the list and start clean instead of relearning every lesson.
The mistakes to avoid
Being too broad
Adding "repair" as a broad negative when you are a repair business is the kind of mistake that turns the tap off completely. Read each negative back to yourself as a sentence: I never want to appear when someone searches for anything containing this word. If that is not true, do not add it.
Blocking your own brand
Careful with words that appear in your own business name or in your key service pages. It happens more often than you would think, usually with a common word like "home" or "care".
Adding and never reviewing
Businesses change. If you take on commercial work next year, the negatives you added this year will quietly stop you from advertising for it. Diary a review every six months.
What good looks like
A healthy account has a negative list that grows steadily and a search terms report that gets less interesting over time. When you open that report and almost everything in it is a search you would happily pay for, the list is doing its job, and your budget is going on people who might actually pick up the phone.