Add negative keywords before you raise bids. In Bing Ads, now Microsoft Advertising, they are one of the fastest ways to stop paying for searches that were never going to become leads, trials, calls, bookings, or sales.
TLDR: Negative keywords tell Bing Ads which searches should not trigger your ads, so your budget goes toward people with stronger buying intent. For example, a plumbing company bidding on “emergency plumber” might block “jobs,” “salary,” “DIY,” and “free,” cutting irrelevant clicks by 28% in one month. In one small service campaign, adding 64 negatives reduced cost per lead from $91 to $63 while keeping lead volume nearly flat. The goal is simple: pay for intent, not curiosity.
Why negative keywords matter in Bing Ads
Bing Ads can bring high-value traffic, especially in B2B, home services, finance, software, healthcare, and local search. The audience is often older, more desktop-heavy, and sometimes closer to purchase than users on other channels. That can be great.
But poor keyword control gets expensive fast. A keyword like “accounting software” can match searches such as “free accounting software for students,” “accounting software jobs,” or “how to build accounting software.” Those users may click. They may even spend time on the page. But many will never buy.
That is where negative keywords help. They give your campaign a filter. They remove mismatched intent before the click happens.
What negative keywords actually do
A negative keyword blocks your ad from showing when a search query contains a term you want to exclude. If you sell premium running shoes, you may want traffic for “buy running shoes,” but not “used running shoes,” “running shoes repair,” or “free running shoes.”
In Microsoft Advertising, negatives can be added at several levels:
- Campaign level: Best for broad exclusions that apply to every ad group in a campaign.
- Ad group level: Best for shaping intent between tightly themed ad groups.
- Shared negative keyword lists: Best for reusable blocks across several campaigns.
The catch is that negative keyword work is never really “done.” Search behavior changes. New product names appear. Competitors launch campaigns. People type weird stuff. Honestly, some query reports look like someone sneezed into the search bar.
Control search intent, not just keywords
The biggest mistake is treating negatives as a cleanup task. They are more than that. They are an intent control system.
Every search has a motive. Some searches show buying intent. Others show research, education, employment interest, support needs, or pure confusion. Your job is to spot which motives are worth paying for.
Here are common intent categories you may want to block:
- Job seekers: “jobs,” “careers,” “salary,” “hiring,” “resume,” “internship.”
- Freebie hunters: “free,” “cheap,” “coupon,” “torrent,” “download.”
- Students and researchers: “definition,” “examples,” “PDF,” “essay,” “course.”
- DIY users: “how to,” “template,” “do it yourself,” “manual.”
- Support traffic: “login,” “customer service,” “phone number,” “refund.”
- Wrong audience: “wholesale,” “used,” “repair,” “parts,” “second hand.”
Not every term is bad for every advertiser. A software company may want “free trial,” but not “free download crack.” A law firm may want “consultation,” but not “law school.” Context matters.
Phrase vs. exact negative keywords
Microsoft Advertising mainly uses negative phrase match and negative exact match. Pick the wrong one, and your filter may be too weak or too aggressive.
- Negative phrase match: Blocks searches that contain the phrase in the same order. If you add free trial, you can block “free trial CRM” and “best free trial CRM.”
- Negative exact match: Blocks only that exact search, or very close to it depending on platform behavior. If you add [crm], you block that broad, vague query without blocking “crm software pricing.”
Use phrase match for obvious bad intent. Use exact match when a query is too broad but related searches may still be useful.
It drives me crazy when advertisers add “free” as a campaign-wide negative without checking the offer. If the landing page promotes a free consultation, free quote, free demo, or free shipping, that single negative can choke off good traffic. Five seconds of cleanup can cause five weeks of weak volume.
How to find negative keyword ideas
Your best source is the Search terms report. It shows the real searches that triggered your ads. Do not rely only on guesses from a spreadsheet.
Review queries with these questions:
- Did this query match the offer? If not, block it.
- Did the user likely want to buy? If not, consider blocking it.
- Did it spend money with no conversions? If yes, inspect it closely.
- Is it a competitor, support, or job query? Route it or exclude it.
- Could it belong in another campaign? Add it as a negative here, then target it there.
Sort by spend first. Then sort by clicks. Then sort by impressions. High-spend bad queries hurt now. High-impression bad queries can hurt click-through rate and quality signals over time.
Build a starter negative keyword list
A starter list saves money from day one. Keep it simple. Add only terms you are confident do not fit your offer.
For many lead generation campaigns, start with groups like these:
- Employment: jobs, job, career, careers, salary, salaries, hiring, recruiter, resume.
- Education: school, degree, class, training, certification, textbook, quiz, exam.
- Low-value intent: free, cheap, lowest price, sample, template, example.
- Research terms: meaning, definition, statistics, history, guide, PDF.
- Support terms: login, sign in, support, help desk, cancellation, complaint.
Be careful with broad business terms. A B2B SaaS brand should not blindly block “demo,” “trial,” or “pricing.” Those can be high-intent searches. A local contractor should not blindly block “near me,” because that may be gold.
Use negatives to separate campaigns
Negative keywords are also useful for campaign structure. Say you have one campaign for brand terms and another for non-brand terms. Add your brand name as a negative in the non-brand campaign. This keeps reporting clean.
You can also separate intent tiers. For example:
- High intent campaign: “buy,” “quote,” “pricing,” “near me,” “book.”
- Research campaign: “best,” “compare,” “reviews,” “alternatives.”
- Blocked from high intent: “what is,” “ideas,” “examples,” “free.”
This helps you bid based on value. A query like “CRM pricing for small business” should not be treated the same as “what is CRM.” Both may matter. They do not deserve the same bid.
Measure the effect
After adding negatives, compare performance over a clean period. Seven days can be too short if volume is low. Two to four weeks is better.
Watch these metrics:
- Click-through rate: Often rises when irrelevant impressions drop.
- Conversion rate: Should improve as intent gets cleaner.
- Cost per conversion: This is the big one.
- Search impression share: Make sure you did not block too much.
- Conversion volume: Efficiency is useless if leads vanish.
A realistic win might look like this: spend drops from $4,200 to $3,650, conversions move from 48 to 51, and cost per lead falls from $87.50 to $71.57. That is not magic. It is just fewer bad clicks.
Common mistakes to avoid
- Blocking too aggressively: Do not remove useful research terms if your sales cycle is long.
- Ignoring match type: Phrase negatives can block more than expected.
- Forgetting plurals and variants: Check reports for odd spellings, abbreviations, and alternate wording.
- Using one list for every campaign: A bad term in one campaign may be valuable in another.
- Never revisiting the report: New waste appears every week.
How often should you update negatives?
For new campaigns, check search terms every two or three days during the first two weeks. After that, weekly reviews are usually enough. Large accounts may need a faster rhythm, especially after budget increases, keyword expansions, or new broad match tests.
Keep a log of major negative additions. If performance drops, you need to know what changed. Do not rely on memory. Paid search has too many tiny switches, and one careless negative can hide a strong query.
Negative keywords do not make Bing Ads perfect. They make it less wasteful. They help your ads appear for people who are more likely to act, not just people who happen to type a related word. Start with clear intent filters, review real search terms, and trim waste before it drains the budget.