How to Optimise PMAX Campaign Structure for Better Results

There’s an ongoing debate among performance marketers about how much campaign structure actually influences the results of Performance Max (PMAX) campaigns. Some folks will tell you to slap everything in one campaign and let Google’s tech take over. Others (myself included) have seen firsthand how a thoughtful setup gives you the power to drive better return on ad spend, keep your data squeaky clean, and avoid some real nasty surprises down the road.

Let’s dive in and break down what I’ve learned from years in the trenches with PMAX. Mistakes, lightbulb moments, and the not-so-obvious details that really move the needle.

Why Campaign Structure Actually Matters for PMAX

Here’s the reality: PMAX, for all its glorious automation, is only as smart as the signals and segmentation you feed into it. If your campaign structure is messy, you’re not just making life harder for yourself. You’re feeding Google mixed signals, muddying your reporting, and leaving money on the table.

Take it from someone who’s rebuilt more than a few shambolic PMAX setups for clients that couldn’t explain why their product A sales kept cannibalising product B. Structure brings clarity: not just in reporting, but in control. Want to see which product categories are scaling profitably? Run targeted, split asset groups or campaigns. Facing pressure on a specific geo? Break it out, track it separately, optimise accordingly.

Cleaner data isn’t just a neat spreadsheet for your Thursday review. It’s the difference between scaling up efficiently or guessing blind.

Breaking Out Asset Groups: Aligning with Real-World Goals

One of the best moves I ever made as a PMAX manager was shifting from a “one-size-fits-all” mentality to a strategy that mirrored real business objectives. Here’s what that looks like in practice:

For Shopping Objectives

• Segment asset groups by product type, margin band, or top sellers. I’ve had great results by putting high-volume, margin-rich SKUs in their own campaign or asset group.
• Keep an eye on seasonalities. Breaking out based on season-specific product groups can radically improve visibility and control.

Lead Gen and Service-Based Goals

• Build asset groups around different service offerings or verticals. Discovery campaigns taught us the value of tight targeting. PMAX rewards the same discipline.
• Use distinct audience signals for each group (don’t sweat, I’ll get into those next).
• For offline conversions. Separate by geo region or franchise if those matter for your reporting.

Geographical Targeting

There’s nothing like watching one region tank your blended ROAS while everyone else is humming along. If you serve distinct locations or countries, split them out. This keeps your budget tight and your automations smart.

The Mighty Audience Signal: Refinement is Power

It’s wild how often I see campaigns still relying on the default “All users” or some old in-market audience list hastily plugged in. Updating audience signals, in my experience, absolutely makes a difference. Especially during learning phase.

Start with intent-driven segments:
– Layer your strongest first-party audiences (think: converters, email subscribers, high-value site visitors).
– Mix in Google’s detailed demographics for context.
– Don’t be afraid to test and tweak. I’ll routinely refresh signals every few weeks and watch for performance swings.

What the research suggests is that better, fresher audience signals accelerate PMAX’s learning cost-effectively. It’s not a “set and forget” box to tick.

Avoiding Cannibalisation: Standard Shopping and Search

This is a trap I’ve seen even experienced teams fall into. Letting PMAX overrun your carefully-built Standard Shopping or even branded search campaigns. Google claims PMAX will only step in when it expects better results, but real-world data often shows some overlap.

Here’s what actually works:
– Pause overlapping Standard Shopping if PMAX is humming, but keep a close eye via placement and search term reports.
– For high-value branded or exact-match Search, set up exclusions and keep those efforts ring-fenced.
– Regularly check search term insights to see if cannibalisation is happening. Don’t blindly trust the system. Transparency is your friend.

Smart Use of Negative Keywords and Exclusions

Negative keywords weren’t always available in PMAX, but now account-level exclusions let you filter out those completely irrelevant or damaging queries. This protects ROAS and keeps creative spend on the right track.

• Maintain a master account-level negative list curated by regular search term reviews.
• If your PMAX campaign is bleeding into unrelated verticals (I once caught ads popping up for competitor brand terms. Ouch), use negatives to shut it down, fast.
• Remember to revisit your lists every quarter. As businesses evolve, so does irrelevant traffic.

Pulling It All Together: Real-World Lessons

Early days with PMAX were a hot mess for a lot of us. Opaque data, unpredictable shifts in spend, attribution chaos. The campaigns that rose above? Every single one had a structure designed around actual business priorities, not just technical limitations.

When clients ask the eternal question, “How do I scale without losing control?” I’ll always push for:
– Segmentation that reflects actual business units, not just Google’s recommended groupings
– Active, ongoing audience management
– Laser focus on search term insights and exclusions

PMAX promises smart automation, but only rewards the diligent. If you give it thought, discipline, and regular attention, you’ll get more than just cleaner reports. You’ll get better results.

So, if you’re tired of drowning in vague attribution reports or seeing costs balloon with no clear answer, start at the foundation. Get your structure right and watch how much more sense everything starts to make.

Your next step? Crack open your PMAX builds. Map out what matters for your business, and start segmenting. The time saved tomorrow is worth the grind today.

Frequently Asked Questions

What’s the ideal number of asset groups in a PMAX campaign?

The “ideal” number varies based on your goals and account size. Lean towards one asset group per distinct product line, service category, or geo, but avoid over-segmentation (e.g., dozens of tiny groups with low spend). Aim for focus and clarity, not clutter.

Can I still use Standard Shopping with PMAX?

Yes, but you need to monitor overlaps. PMAX generally takes precedence, but there are scenarios where Standard Shopping can complement it. Like with specific product or audience targeting. Use separate budgets and regular performance reviews to prevent cannibalisation.

How important are audience signals really?

They’re crucial, especially when launching or scaling new campaigns. Robust audience signals help Google’s system learn faster and optimise more accurately. Update and refine them regularly for best results.

Will negative keywords restrict PMAX too much?

Not if you use them wisely. Account-level exclusions help filter out irrelevant traffic without hampering your core opportunities. Regular analysis is key. Overblocking can limit reach, underblocking wastes spend.

How often should I restructure my PMAX campaigns?

There’s no universal rule, but most live accounts benefit from a review every two to three months, or whenever business goals, product range, or external market factors shift. Don’t let campaigns run stale. Fresh structure keeps performance sharp.