Broad match and Smart Bidding: when it works and when to pull back

Key takeaways

Broad match only makes sense with Smart Bidding. Google itself strongly recommends against using it with manual bidding.
Broad match finds more of whatever you count as a conversion. If your conversions are junk form fills, it will find more junk.
Test it with a broad match experiment before you switch a whole campaign, and give it at least one or two full conversion cycles.
Pull back when cost per real customer rises, irrelevant search terms grow faster than you can block them, or budget shifts away from your best keywords.

Your Recommendations page says to add broad match keywords. The estimate promises more conversions. But you remember broad match from a few years ago, when it showed your ads for searches that had nothing to do with your business.

Broad match and Smart Bidding work differently now, and for some accounts the pairing does deliver more conversions at the same cost. For others it quietly spends more on weaker traffic. This article explains how broad match works with Smart Bidding today, what you need in place first, how to test it without betting the account, and the signs that tell you to pull back.

How broad match works with Smart Bidding now

Broad match is the default match type in Google Ads. A keyword typed without brackets or quotes is a broad match keyword. It can match searches related to your keyword, not just close variants, so it reaches more queries than phrase or exact match.

The reason Google pairs it with Smart Bidding is auction-time bidding. Smart Bidding sets a bid for each individual search, using signals available at the moment of the auction. Without Smart Bidding, every search that broad match catches gets the same bid you set by hand. That is why Google says it strongly recommends broad match only with Smart Bidding, even though the recommendation can technically apply to manual bidding campaigns.

The strategies that qualify are Maximize conversions, Maximize conversion value, Target CPA and Target ROAS. With these, Google says you no longer need to split keywords into separate ad groups by match type.

What Google claims, and what that means for you

Google’s help page cites its own 2020 internal data: advertisers who switched phrase match keywords to broad match saw about 25% more conversions in Target CPA campaigns and about 12% more conversion value in Target ROAS campaigns while meeting their targets. Treat this as Google’s average across advertisers, not a forecast for your account. It also counts conversions, not sales. Your result depends on what you track as a conversion.

Where AI Max fits

Google is folding broad match into AI Max for Search campaigns, a campaign setting that adds broad match expansion, keywordless matching, text customization and final URL expansion. Google’s help page says campaigns using the old campaign-level broad match setting are being upgraded to AI Max automatically starting September 2026. Negative keywords are still respected with AI Max turned on. Everything below about conversion quality, testing and negatives applies to AI Max too.

What you need before you switch

Broad match multiplies the quality of your conversion data, good or bad. Check these four things first.

Conversion tracking that measures what matters. Google’s bidding guide says Smart Bidding works best with a solid base of conversion data that includes every conversion action that matters to your business. If your primary conversion is a page view or a button click, fix that first.
Conversion quality you can trust. If half your form fills are spam or tire-kickers, broad match will happily find more of them. Import qualified leads or sales from your CRM if you can, and make those your primary conversion.
Enough volume for Smart Bidding to learn. Google doesn’t publish a single minimum for broad match. As an illustrative editorial rule, not a Google requirement, we’re cautious in campaigns with fewer than about 30 conversions a month, because results swing too much to read.
Some budget headroom. Google notes you may need a larger budget to reach its estimates. If your campaign is already limited by budget, broad match competes for the same dollars as your proven keywords.

Also check your conversion cycle. Google defines it as the time between a click and the conversion, plus the time for imported conversions to show up. If most of your leads convert in two days, Smart Bidding adapts in about two days. If they take three weeks, every test takes longer.

How to test broad match safely

Don’t flip every keyword at once. Use an experiment so you have a fair comparison.

Option 1: a broad match experiment

Google’s broad match experiments split traffic and budget evenly inside your existing Search campaign. The control keeps your current keywords. The trial gets your current keywords plus broad match versions of them. To set one up:

Go to Campaigns, then Experiments.
On the Add broad match keywords card in the recommended experiments section, select Create experiment. You can also start from the plus button, choose Campaign features and settings, then Broad match keywords for Search campaigns.
Set the start and end dates and name the experiment.
Decide whether to apply the changes automatically if results are favourable. For a first test, leave this off and decide yourself.

You can’t use this type of experiment if the campaign uses a portfolio bid strategy or a shared budget, targets the Display Network, already has an active trial, uses certain legacy features, or doesn’t use a Smart Bidding strategy. In those cases, use a custom experiment, which copies the campaign into a separate trial.

Option 2: a custom experiment

Go to Experiments, select the plus button and choose Custom. You choose how much of the original budget goes to the experiment, and you can pick a cookie-based split so each user only sees one version. Google warns that a custom trial may need longer to ramp up.

Rules for a fair test

Don’t edit the campaign or the trial while it runs. Google says changes make results harder to read.
Judge it on cost per qualified lead or sale, not just conversions.
Wait at least one or two full conversion cycles after launch before reading results. As an illustrative guide, plan for four to six weeks in most lead-gen accounts.
Pick your success metric before you start, and write down what result would make you stop.

Monitor search terms and add negatives

Broad match makes the search terms report your most important weekly task. Go to Campaigns, then Insights and reports, then Search terms. Turn on the Keyword column, which is hidden by default, so you can see which broad keyword caught each search.

Google omits search terms without enough query activity, so you won’t see everything. Search terms insights groups some of those into themes, which can help you spot a whole category of bad traffic.

A weekly routine for the first month:

Sort by cost. Review every term that spent more than your target CPA without converting.
Add irrelevant terms as negatives. Put terms you never want into a shared list so every campaign benefits. Our guide to negative keyword lists every Canadian account should start with covers the starter lists.
Check for competitor and brand searches you didn’t expect. If the campaign uses AI Max, brand exclusions can block searches for brands you list.
If you advertise in Quebec, review French search terms separately. Your English negatives won’t catch French wording.
Look for searches outside the area you serve, like US cities or provinces you don’t ship to.

Signs to pull back

What you see	What it usually means	What to do
Conversions up, but sales or qualified leads flat	Broad match is finding easy, low-quality conversions	Stop the trial. Fix conversion quality before testing again.
New irrelevant search terms every week, faster than you can block them	Your keywords or landing pages are too vague for the system to read your intent	Narrow the broad keywords to your strongest themes, or return those ad groups to phrase match.
Spend shifting away from proven exact match keywords	Broad keywords are competing for the same budget	Check budget limits. Keep exact match on your best terms.
CPA above target after two conversion cycles	The trial isn’t beating the control	End the experiment and don’t apply it.
Bid strategy status stuck on limited or learning	Not enough conversion data	Consolidate campaigns or wait for more volume.

A worked example

The numbers here are illustrative. A Calgary renovation company spends $6,000 CAD a month on Search with Target CPA. Its control arm produces 45 form fills at $67 each. The broad match trial produces 56 form fills at $54 each. On conversions alone, broad match wins.

Then the owner checks the CRM. The control’s leads booked 14 estimates. The trial’s leads booked 12. Cost per booked estimate was about $215 in the control and about $252 in the trial. Broad match bought more leads and fewer real jobs. The right move is to keep the control, import booked estimates as a conversion, and test again later.

When not to use broad match

You bid manually or with Maximize clicks.
Your conversion tracking counts actions that don’t predict revenue.
Your campaign gets only a handful of conversions a month.
Your budget is already capped and your exact match keywords aren’t getting all the impressions they could.
You’re in a sensitive category where a stray match could cause a policy or reputation problem.

Decision checklist

Is the campaign on Maximize conversions, Maximize conversion value, Target CPA or Target ROAS?
Is the primary conversion a real business outcome, or a qualified lead imported from your CRM?
Does the campaign get enough conversions a month to read a test?
Is there budget headroom, or are you willing to add it?
Have you set up a broad match or custom experiment instead of switching outright?
Have you blocked time each week to review search terms and add negatives?
Have you written down the result that would make you stop?

If you answered no to any of the first three, fix that before you test broad match. If you answered yes to all seven, set up the experiment this week.

Sources: Your guide to broad match, Google Ads Help · Grow your Smart Bidding campaigns with broad match, Google Ads Help · About broad match experiments, Google Ads Help · Set up a custom experiment, Google Ads Help · How our bidding algorithms learn, Google Ads Help · About the search terms report, Google Ads Help · About the broad match keywords campaign setting, Google Ads Help · Frequently asked questions about AI Max for Search campaigns, Google Ads Help

Platform details as of November 2026.