Performance Max (PMax) campaigns have changed how advertisers run ads on Google Ads. Instead of managing multiple campaign types separately, PMax combines them all—Search, Display, YouTube, Gmail, Discover, Maps, and Shopping—into a single, AI-driven campaign. Google’s machine learning takes the wheel, optimizing placements and bidding to drive conversions.

Sounds great, right? Well, yes and no.

PMax can be a game-changer for performance marketers, helping them reach more customers with less manual work. But there’s a catch: control. Because Google’s automation makes decisions behind the scenes, advertisers often struggle with transparency. Where’s the budget actually going? Are you attracting real customers or wasting money on low-quality traffic?

That’s the challenge: how do you maximize ROI while keeping control over your ad spend? Google made some enhancements, but there’s still room for improvement. Meanwhile, this guide will help you make the most of PMax campaigns without letting Google’s automation run wild with your budget.

Best Strategies to Improve ROI in PMax Campaigns

Maximizing ROI in PMax campaigns isn’t just about setting them up and hoping for the best. Since Google’s AI makes many decisions on your behalf, advertisers need to structure their campaigns strategically, fine-tune bidding, and feed the system with the right data. Here are the best strategies to get the most out of PMax while staying in control.

1. Optimize Campaign Structure

Many advertisers make the mistake of running a single PMax campaign with multiple asset groups without realizing the impact on performance. While this can work in some cases, a well-structured campaign setup can improve targeting and budget allocation.

You should run multiple PMax campaigns when: 

  • You have distinct products or services with different margins.
  • You need to allocate budgets differently based on product priority.
  • You want better control over performance tracking by segmenting campaigns.

On the other hand, use a single campaign with one asset group when: 

  • Your budget is small, and segmenting would limit data collection.
  • All products or services share similar goals and audience targeting.
  • You want Google’s AI to have maximum flexibility to optimize performance.

2. Leverage the Right Bidding Strategy

Your bidding strategy dictates how Google prioritizes conversions and allocates budget. The two most common options for PMax are Max Conversion Value and Max Conversions—but which one is better?

  • Max Conversion Value: Best if you care about profitability over volume and have different conversion values (e.g., high-ticket vs. low-ticket items).
  • Max Conversions: Ideal if you’re focused on generating the highest possible number of conversions, regardless of value.

Pro tip: If you have a clear Target ROAS (Return on Ad Spend) or Target CPA (Cost per Acquisition), set them accordingly. But be careful—being too aggressive with these targets can limit ad delivery.

3. Use Audience Signals Strategically

Audience signals are one of PMax’s most misunderstood features. While Google’s AI ultimately decides who sees your ads, providing the right audience signals helps the system learn faster and target more relevant users.

Most advertisers struggle with audience signals because: 

  • They don’t use them at all, thinking Google will figure everything out.
  • They use too many broad signals, which dilutes targeting.
  • They ignore first-party data, missing out on high-intent users.

If you want to use audience signals effectively, follow these steps: 

  • Prioritize first-party data (website visitors, CRM lists, engaged audiences).
  • Use custom segments based on search intent rather than just demographics.
  • Avoid overloading with irrelevant signals—stick to data that reflects real purchase intent.

4. Set Proper Conversion Thresholds

PMax campaigns rely on machine learning, and without enough conversion data, performance suffers. Google recommends at least 30–50 conversions per month per campaign to allow AI to optimize effectively. But ideally, 60+ conversions give the system enough data to make smart bidding decisions.

If you don’t have enough conversion volume, Google’s AI struggles to identify patterns and optimize bids and this lack of consistency in data affects performances. Additionally, budgets may be wasted on low-intent users due to poor AI learning.

5. Balance Asset Selection

PMax campaigns allow you to use text, images, and videos across multiple placements (Search, Display, YouTube, Shopping, Gmail, Discover, and Maps). But does using all asset types always make sense?

When NOT to use every asset type:

  • If a specific format doesn’t align with your brand messaging (e.g., you don’t want auto-generated videos).
  • If your audience responds better to certain placements (e.g., Shopping-heavy campaigns may not need Display assets).
  • If you prefer more control over messaging rather than letting Google decide.

Another important aspect of improving ROI on PMax campaigns is ensuring you have high-quality assets in hand. Poor creatives can lower engagement and hurt performance. And since Google prioritizes high-performance assets, these low-quality creatives will get limited exposure. 

Don’t forget to use videos! If you don’t upload one, Google will generate one for you (which may not align with your brand).

What Not to Do in PMax Campaigns

When ideating and setting up PMax campaigns, many advertisers make avoidable mistakes that end up limiting performance instead of improving it. Here’s what not to do when running PMax campaigns:

Overloading Campaigns with Too Many Asset Groups

Many advertisers assume that adding multiple asset groups will give them better control over targeting. In reality, this can dilute performance and make it harder for Google’s AI to optimize effectively.

Why too many asset groups can hurt performance:

  • Google distributes budget across all asset groups, even low-performing ones.
  • Less data per asset group means slower learning and optimization.
  • It becomes harder to identify what’s working when results are scattered.

✅ What to do instead:

  • Keep asset groups focused and relevant to a specific audience or product.
  • Only create multiple asset groups if they have distinct messaging or creative assets.
  • Let Google prioritize top-performing assets instead of forcing too many variations.

Relying on PMax Without Supporting Search & Shopping Campaigns

While PMax is powerful, it’s not a one-size-fits-all solution. Many advertisers assume they can switch entirely to PMax and ditch their Search and Shopping campaigns—this is a big mistake.

Why PMax shouldn’t be your only campaign type:

  • Less visibility into search queries (PMax doesn’t provide full keyword data).
  • PMax prioritizes conversions, which means it might ignore high-intent keywords that don’t convert right away.
  • You lose manual control over bids, placements, and exclusions.

✅ What to do instead:

  • Run Search campaigns alongside PMax for more control over high-performing keywords.
  • Use Shopping campaigns (if applicable) to ensure visibility in Google’s product listings.
  • Test brand campaigns separately to avoid cannibalization (PMax may prioritize branded traffic).

Not Being Cautious with Exclusions

Exclusions are a useful tool, but many advertisers overuse them, thinking they can force PMax to behave like a traditional campaign. This can restrict performance and prevent the AI from optimizing effectively. Here are the main reasons:

  • Blocking too many placements: While some exclusions (like mobile apps) might make sense, removing too many placements can limit reach.
  • Negative keywords in account-level lists: PMax ignores campaign-level negative keywords unless added via a Google Rep (so exclusions might not work as expected).
  • Over-filtering audiences: Restricting who can see your ads too much can slow down AI learning.

✅ What to do instead:

  • Use account-level negative keywords to block irrelevant searches (but don’t go overboard).
  • Be selective when excluding placements—monitor performance first before making drastic changes.
  • Let PMax collect enough data before making exclusion decisions.

Investing Heavily in Audience Signals & Search Themes Without Testing

Audience signals and search themes help guide PMax’s AI, but they’re not hard restrictions. Many advertisers overinvest in these settings, expecting them to act like traditional targeting.

However, audience signals don’t limit who sees your ads. Instead, Google uses them as a starting point but can expand beyond them. Furthermore, search themes guide AI but don’t function like keywords—Google may still show ads for related (or even unrelated) queries.

It’s also important to note that overloading your campaigns with too many audience signals can confuse the algorithm instead of improving targeting.

✅ What to do instead:

  • Start with high-quality audience signals (first-party data, custom segments, engaged users).
  • Use a few relevant search themes—don’t overload with dozens of them.
  • Test small changes before making major adjustments.

By avoiding these common mistakes, you’ll let Google’s AI work more effectively, prevent wasted ad spend, and get better ROI from your PMax campaigns.

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Budget Allocation for Maximum ROI

One of the most crucial decisions in managing PMax campaigns is how to allocate your budget. With PMax bringing in a wide range of ad placements, it’s easy to wonder how much of your total ad spend should go to it versus other campaign types. 

The exact budget split depends on your business goals, but a good starting point is balancing between PMax and your traditional campaigns (Search and Shopping) based on how much control you need over targeting. As general guidelines: 

  • PMax for broad visibility and conversions: If you’re aiming for brand awareness and maximizing conversions across multiple channels, allocate 40-60% of your budget to PMax.
  • Search and Shopping for high-intent traffic: Keep 30-50% of your budget focused on Search and Shopping campaigns, as these can help you capture customers with higher purchase intent.

For new products or brand awareness, lean more on PMax since it casts a wider net. But, for highly competitive products or when you’re targeting specific keywords, keep a bigger portion of your budget focused on Search and Shopping campaigns.

Ideal Budget Distribution for Conversions and CPA

To improve your conversion rates and reduce CPA, a balanced budget distribution also works best. Follow this recommendation: 

  • 40-50% to PMax: Perfect for driving a wide range of conversions across different platforms.
  • 25-40% to Search campaigns: Crucial for targeting high-intent keywords with a clear purchase intent.
  • 15-20% to Shopping campaigns: Best for e-commerce businesses looking to showcase products directly on Google’s shopping platform.

With this split, PMax will get you the broadest coverage, reaching potential customers across channels like YouTube, Gmail, and Display. Meanwhile, Search campaigns will capture people actively searching for your products or services, delivering more qualified leads, and Shopping campaigns will ensure you’re showing up for e-commerce queries, helping product visibility and sales.

Key Takeaways

To run profitable PMax campaigns, start by optimizing your campaign structure and carefully selecting asset groups. Remember, the right bidding strategy and a balanced budget allocation are key to driving the best ROI. Don’t rely only on audience signals and exclusions—these should be used strategically and tested to make sure they’re really working for you.

Focusing on conversion thresholds and choosing the right mix of assets (text, video, and images) can also make a big difference in your campaign’s success.Lastly, continuous testing and optimization are essential. As with any PPC campaign, the landscape is always changing, and it’s crucial to stay on top of performance metrics, budget allocation, and asset quality. Regularly monitor your campaigns, adjust bidding strategies, and test new assets to see what works best for your audience.