Performance Max: What to Actually Do With It

No campaign type generates more confused questions from store owners than Performance Max. “PMax is spending everything on my brand.” “I have no idea what it is actually doing.” “Should I run it alongside Standard Shopping, or only PMax?”

That confusion makes sense. PMax is built to hide the controls advertisers used to depend on. That does not mean you have lost all control. It means the levers have moved, and once you know where they sit, PMax becomes much easier to manage.

What PMax Actually Is

Performance Max is a goal-based campaign that runs across every part of Google’s inventory at once (Search, Shopping, Display, YouTube, Gmail and Maps) from a single campaign. You supply assets (images, videos, headlines, descriptions and your product feed) plus a conversion goal, and Google’s automation decides where your ads appear, who sees them and which creative they get.

For eCommerce stores linked to Merchant Center, PMax is effectively the successor to Smart Shopping, which Google retired in 2022. Your product feed powers the Shopping side, and Google adds Display and YouTube placements using the creative assets you upload.

That is why stores running PMax find it spending in places they never chose. It is working as designed. The trade-off is that Google spreads budget across the channels where it expects conversions, which can help or hurt depending on how good your conversion data is.

Asset Groups: How PMax Is Structured

Standard Shopping has ad groups. PMax has asset groups: bundles of creative (headlines, descriptions, images and videos) combined with audience signals and a selection of products from your feed.

A single PMax campaign can hold several asset groups, and this is where most of your strategic control lives.

Structuring asset groups:

A common approach is to split asset groups by product category or margin tier. A clothing store might have one for outerwear, one for footwear and one for accessories, each with headlines, images and audience signals that match its category.

Another approach splits by stage of intent: one asset group with prospecting signals (interests and in-market audiences) and another with retargeting signals (customer lists and site visitors).

Neither is right for everyone. The best structure depends on the size of your catalogue, how much creative you can produce, and whether you have enough conversion data for Google to optimise at asset group level.

Reporting on asset groups:

PMax does not give you impressions or conversions per asset group the way Standard Shopping reports by ad group. This is one of the fairest complaints about PMax: transparency really is limited. You get a low, good or best rating for each asset, but no spend or conversion figures per asset group.

The workaround is to run a separate PMax campaign for each major product category if you need clear performance data by category. You give up some efficiency (budget can no longer flow freely between groups), but you gain campaign-level results for each category.

Audience Signals: What They Are and How to Use Them

Audience signals are hints you give Google’s algorithm about who is likely to convert. They are not targeting in the traditional sense. Google can and will show ads to people outside your signals if it predicts a conversion there. Treat signals as a starting point, not a boundary.

The signals that make a real difference:

Customer match lists: upload your existing customer emails. This is the strongest signal you can give PMax. Google uses it to find similar new users and to re-engage past buyers. If you have a customer list of any size, use it.

Website visitor lists: GA4 audiences or Google Ads remarketing lists built from site traffic. Segment by high intent behaviour such as product page views, basket abandonment and checkout abandonment. These tell Google that people who act this way on your site are worth reaching.

In-market and custom segments: Google’s in-market audiences (people actively researching your category) or custom segments built from keywords and URLs. They are weaker than first-party signals but useful for prospecting when your customer list is small.

Never leave signals empty. An asset group with no signals makes PMax start from nothing. It will get there eventually, but it will burn more money during learning than it needs to.

Brand Exclusions: The Setting Most Accounts Are Missing

This is the cause of “PMax is spending everything on my brand”. By default, PMax bids on your own brand name in Search inventory. When someone types your store name, PMax takes the click and the conversion, even though that person was already on their way to you.

That inflates ROAS, misrepresents what PMax is really doing, and spends money on traffic you would have won organically or through a brand campaign at a much lower CPC.

Adding brand exclusions:

In the PMax campaign settings, open Brand exclusions. You can exclude specific brand terms from the Search and Shopping inventory within the campaign. Add your brand name, common misspellings and any product line names people search for specifically.

Note that brand exclusions only cover Search inventory inside PMax. It can still appear on branded queries through other inventory. For full brand control, run a separate brand Search campaign and let PMax concentrate on non-branded traffic.

Brand campaign plus PMax:

This is the setup we recommend for most eCommerce stores:

• A dedicated brand Search campaign using exact and phrase match on brand terms, with manual CPC or Maximise Clicks and a modest budget
• A PMax campaign with brand exclusions applied, focused on non-branded acquisition

You get predictable, low cost coverage of brand searches, while PMax works on non-branded demand where its automation has the most room to find growth.

PMax or Standard Shopping?

There is no universal answer to “PMax, Standard Shopping or both?”, but there is a practical way to decide.

Run PMax on its own if:

• Your catalogue is small (under 500 products)
• The account has a healthy conversion history (50+ conversions in the last 30 days)
• You do not need tight control over which products show for which queries
• You are comfortable with less visibility into placement-level performance

Run Standard Shopping alongside PMax if:

• You have high margin products you want to bid hard on without PMax’s budget distribution getting in the way
• You want a Shopping campaign you can exclude from PMax to make a clean performance comparison
• PMax keeps underspending its budget despite having enough conversion data

Run Standard Shopping instead of PMax if:

• The account is newer and gets fewer than 15 to 20 conversions a month (PMax needs conversion data, and without it the automation is close to random)
• You need search term visibility that PMax does not give you
• Shopping is your main channel and you do not want spend spread across Display and YouTube

When both run together, PMax gets priority by default when the same product is eligible for both. To stop PMax from swallowing Standard Shopping, structure them deliberately. A common pattern is to put the core catalogue in PMax and keep a separate Standard Shopping campaign for specific high value segments, with product-level exclusions applied.

The Learning Period

Any significant change to a PMax campaign (a new bid strategy, a budget change of more than 20% or a large batch of new assets) puts it into a learning period of one to two weeks. During that time the data is unreliable and efficiency is lower than normal.

Do not make several big changes at once. Do not judge performance mid-learning. And do not panic and switch the bid strategy again because week one looks bad, because that restarts the learning period.

The most common way PMax fails is someone chasing results during learning, making changes that keep resetting it, and then deciding PMax does not work. With good conversion data and consistent signals, most accounts see PMax settle at reasonable efficiency if it is left alone for four to six weeks.

When PMax Is Not the Problem

Before deciding PMax does not work, check two things.

Conversion tracking quality. PMax optimises towards whatever conversion action you give it. If that action is set up badly (double firing, attributed to the wrong events, not deduplicated, or including micro conversions that are not revenue), PMax is optimising towards bad data and its decisions will look irrational. Better PMax results start with clean conversion data.

Product feed quality. On the Shopping side of PMax, the feed decides which products show and how relevant they are. A weak feed means PMax cannot match products to the right searches, however well the campaign is set up.

If tracking is clean and the feed is complete, PMax usually performs. If either foundation is broken, no campaign setting will fix it.

What to Do Right Now

If you are running PMax and are not happy with the results, check these four things in order:

• Are brand exclusions applied? If not, add them today.
• Are audience signals set? If not, upload your customer list and add your highest intent website visitor audiences.
• Is the conversion action correct? Make sure it tracks real purchases, not add to basket or page views.
• Has the campaign run for at least four weeks without major changes? If not, hold off on optimising and let it run.

If all four check out and performance is still poor after six weeks, that is worth investigating further, starting with an audit of your conversion data.