AI Max for Search Campaigns: What It Is, How It Works, and When to Use It

Google quietly changed the rules of Search advertising, and most accounts haven't caught up. In May 2025, Google introduced AI Max for Search campaigns - a one-click feature suite that brings the company's most advanced AI capabilities directly into standard Search campaigns.

According to Google's internal data, advertisers that activate AI Max typically see 14% more conversions or conversion value at a similar CPA/ROAS.

For campaigns still relying mostly on exact and phrase match keywords, the typical uplift is even higher at 27%.

Those numbers look compelling. But independent testing tells a more complicated story. Monks Agency found that 99% of AI Max impressions generated zero conversions across approximately 30,000 search terms, and a LinkedIn poll of PPC professionals revealed only 16% reporting good performance with the feature. The gap between Google's cherry-picked case studies and real-world practitioner experiences is wide enough that every advertiser needs to understand exactly what this feature does - and doesn't do - before flipping the switch. This guide breaks down AI Max from a practitioner's perspective. No hype, no blanket recommendations. Just the mechanics, the evidence, and a clear framework for deciding whether it belongs in your account.

What AI Max Actually Is (and What It Is Not)

Let's clear up the most common misconception first. AI Max is not a new campaign type. It is an optimization layer you can enable within an existing Search campaign. You don't create an "AI Max campaign" the way you'd create a Performance Max or Display campaign. It's a feature layer you activate within standard Search campaigns. As Google's Ads Product Liaison Ginny Marvin confirmed, your existing campaign settings don't change, including location, budget, and language.

Think of it as an upgrade package for your Search campaigns that bundles three distinct features under a single toggle. It is turned off by default, so you choose when to opt in.

You can then disable individual components like Final URL Expansion or Text Customization in campaign settings if needed.

This is a meaningful distinction from Performance Max. AI Max for Search campaigns is built to have parity with Search on PMax. Both use the latest Google AI, and the main difference is that PMax serves ads across Search and non-Search channels, while AI Max only serves on Search text inventory. You keep the transparency and control of Search campaigns while getting Performance Max-level automation for targeting and creative.

AI Max marks a fundamental shift away from strict keyword syntax and toward pure intent matching, bringing Performance Max capabilities directly into classic Search campaigns. Google has confirmed that AI Max will eventually replace Dynamic Search Ads.

The Three Core Features Under the Hood

AI Max bundles three features that work together but can be managed independently. Understanding each one matters because they carry different risk profiles.

Search Term Matching

This is the headline feature. Search term matching uses Google AI, including broad match and "keywordless" technology, to expand your reach beyond your existing keywords. It learns from your current keywords, ad creatives, and URLs to find new, relevant, and high-performing search queries you might otherwise miss.

The "keywordless" component is key. DSAs and PMax are examples of using keywordless technology - where you don't explicitly enter keywords for targeting. AI Max for Search uses two types of information for keywordless targeting: landing page information (like DSA) as well as targeting based on the content in the ad group including your assets and keywords.

In practice, AI Max effectively "broadmatch-ifies" all your keywords. This is worth sitting with. Even if you've meticulously built exact-match keyword lists, enabling search term matching means Google's AI will use those keywords as directional signals rather than precise constraints.

Text Customization

This feature - formerly known as Automatically Created Assets - uses text from your existing ads, landing page copy, and generative AI to create customized ad copy, headlines, and descriptions that are more relevant to a user's search.

The upside is efficiency at scale. The risk is brand control. Because AI Max can pull from virtually any readable text on your site, advertisers have seen unexpected copy show up in ads. One advertiser even had ad copy generated from image alt text, which led to unfortunate results.

A critical development mitigates this risk. On February 26, 2026, Google announced that text guidelines are now open to all advertisers worldwide, across both AI Max for Search and Performance Max campaigns.

Term exclusions let you specify words or phrases that must never appear in AI-generated ads (up to 25 per campaign, per language). Messaging restrictions allow natural language instructions that guide the AI's overall tone and content, such as "focus on our free trial offer" or "do not mention competitor names" (up to 40 per campaign).

Final URL Expansion

This feature automatically sends users to the most relevant landing page on your website based on their search intent, which can help improve engagement and conversion rates.

In order to use the Final URL expansion setting, Text Customization must be selected. Turning off Text Customization will also disable Final URL expansion.

This feature is enabled by default when you opt in to AI Max. You must manually uncheck the box if you want to turn it off. That's a detail easy to miss. And there's a practical gotcha: when Final URL expansion is turned on, pinned Responsive Search Ad assets aren't used if a more relevant URL is chosen, because they may not match the customer's intent.

For advertisers with tracking templates, verify compatibility before enabling. AI Max helps improve how your ads match search terms and includes dynamic landing pages. However, when combined with existing tracking templates, these dynamic URLs can sometimes lead to broken expanded landing pages with a 404 error.

Real Performance Data: What the Evidence Actually Shows

Google's headline numbers are real but narrow. The gap between best-case and typical results is significant, and understanding why that gap exists matters more than the numbers themselves. The wins are real. ClickUp reported a 20% lift in incremental conversions, 16% higher incremental ROAS, a 22% lower CPA, and a 15% higher conversion rate after scaling AI Max to over 400 campaigns.

Klook saw conversion value increase by 161% and a 25% increase in ROAS within one month.

L'Oréal saw a 2x boost in conversion rates and cut cost-per-conversion by 31%, while MyConnect in Australia added 16% more leads and dropped CPA by 13%.

The struggles are equally real. In a B2B account promoting project management software, AI Max struggled. Despite a reasonable CPC of €0.89, the conversion rate was just 0.76% - making it the worst-performing match type in the account.

Coalition Technologies found a sharp contrast between ecommerce and lead-gen accounts. Ecommerce accounts with strong conversion history consistently had impressive results. The same cannot be said for lead-gen accounts, which performed poorly.

One finding from Search Engine Land's analysis of 23 tests stands out: every successful AI Max test occurred in an account with low-to-no adoption of DSA campaigns. Almost every single capability of DSA campaigns is now available in AI Max, so having both campaign types running in parallel doesn't improve performance.

Another critical insight from that same analysis: using the full package of features - search term matching, text customization, and URL expansion together - can improve the likelihood of success by up to 40%. Going halfway may actually produce worse results than going all-in or staying out entirely.

How to Set Up AI Max (the Right Way)

Setup is straightforward. The strategic decisions around setup are what separate good outcomes from wasted spend.

Go to Settings within the Campaigns menu. Select the Search campaign you'd like to update. Select AI Max in the section menu. Toggle to opt-in to AI Max settings. Select the specific AI Max features you want to use in your campaign.

To get the full benefits of AI Max, turn on both search term matching and asset optimization. When both are turned on, AI Max receives all the signals needed to understand the full context of your business, find the most relevant customers, and drive the best performance.

Before enabling anything, nail the prerequisites:

• Conversion tracking must be solid.

If you use Manual CPC with AI Max, the full benefits will be limited. Search term matching will not work with manual CPC bidding because AI Max relies on signals from automated bidding strategies such as Maximize Conversions or Maximize Conversion Value.

• Landing pages need depth.

AI Max relies on your landing page content to understand relevance and automate assets, so optimize your key pages to include clear, substantial, and well-structured copy.

• Build negative keyword lists proactively.

AI Max fully respects negative keywords at both campaign and account levels. You maintain complete control over search terms you want to exclude.

• Use URL exclusions.

Brand and URL exclusions are vital for guiding AI Max in the right direction. There's a high risk of wasted spend if you don't exclude irrelevant and low-value pages.

For testing, Google Experiments splits traffic 50/50 between one campaign with AI Max enabled and one without, giving you a clear comparison.

Run for 4+ weeks minimum - a 2-4 week learning period plus 2+ weeks for evaluation.

When AI Max Makes Sense (and When It Doesn't)

Not every account benefits equally. The pattern across independent testing is remarkably consistent. Enable AI Max when:

• You run ecommerce campaigns with strong conversion data.

AI Max is suitable for mature ecommerce campaigns with strong site content and stable conversion tracking.

• You've exhausted exact and phrase match growth.

AI Max, like broad match, thrives on sufficient budget. If you're currently maxed out on exact match opportunities and want to grow, AI Max presents a viable path.

• Your website has comprehensive, well-organized content across multiple product or service pages - giving Final URL Expansion good pages to work with.
• You have at least 30 conversions per month to give Smart Bidding enough signal to optimize.

Hold off when: - Lead-gen accounts should keep the toggle off, at least for the time being. Even accounts with substantial conversion data underperformed due to ambiguous or weaker quality signals.

• Text customization is not recommended if you have very strict brand guidelines or operate in sensitive industries, or if your website changes often without corresponding ad updates.
• You're already running DSA ad groups in the same campaign. Consolidate first.

Machine learning takes time to learn and optimize. You might experience poor performance initially. This becomes challenging if you have strict CPA targets or a limited budget.

AI Max vs. Performance Max vs. Standard Search: Picking the Right Tool

These three approaches occupy distinct positions. Thinking of them as interchangeable leads to budget waste and reporting confusion.

AI Max bridges the gap between standard Search campaigns and Performance Max campaigns, offering the same level of automation with new control features. Standard campaigns offer better control but demand significant time. Performance Max is fully automated and offers low control and transparency.

Standard Search remains your anchor for precision. Brand terms, competitor terms, and tightly scoped campaigns where every query must be intentional. No AI override needed. AI Max for Search is your expansion lever. Same Search inventory, but with AI-powered discovery of queries you'd miss otherwise. You retain search term reports, negative keyword control, and ad group-level visibility. Performance Max covers the full funnel across all Google inventory - Search, YouTube, Display, Gmail, Maps, and Discover. AI Max is a feature suite that enhances existing Search campaigns. Performance Max is a separate campaign type that runs across all Google channels. They are designed to work together, but they operate differently and carry different risk profiles.

Google now promotes the "Power Pack" - three campaign types working in concert: Demand Gen creates awareness and interest. AI Max engages users on Search to capture and convert intent. Performance Max orchestrates full funnel performance at scale.

For practical budget allocation, the framework varies by business model. E-commerce accounts often benefit from heavier Performance Max investment (60-70% of budget) with AI Max handling Search-specific expansion. B2B and services accounts may invert that ratio, keeping 30-40% in Performance Max and relying more heavily on AI Max-enhanced Search where intent signals are clearest.

The Controls That Make AI Max Manageable

Google shipped AI Max with more controls than Performance Max ever had at launch. Knowing which levers exist - and pulling them - determines whether the feature works for you or against you.

Unlike Performance Max, AI Max provides new controls for precision: location of interest targeting at the ad group level, brand settings for inclusions and exclusions, URL inclusions and exclusions for landing pages, and text guidelines for term exclusions and messaging restrictions.

Brand controls operate at two levels. At the campaign level, you set brand exclusions to prevent ads from appearing alongside competitor brands. At the ad group level, you can specify brand inclusions to target users interested in specific brands.

Text guidelines are the newest and most impactful control. The practical implication is worth noting for advertisers who kept text customization off due to concerns about creative control. Enabling text guidelines provides a structured mechanism to reintroduce that control, making text customization significantly safer for brands with strict messaging requirements.

Reporting addresses Performance Max's biggest weakness. The search terms report now includes "AI Max" as a distinct match type indicator. When you see AI Max in the match type column, you know that term came from AI-powered expansion rather than your traditional keyword targeting. A new source column indicates whether the match originated from broad match expansion or keywordless matching.

Combined reporting views show search terms alongside the headlines that served and the URLs users visited, letting you trace the complete customer journey from query through ad creative to landing page.

A Practitioner's Playbook for Testing AI Max in 2026

For most advertisers, the right approach in 2026 is not full adoption across every campaign. It is structured testing. Use AI Max where the account has earned the right to scale.

Here's a phased approach that balances ambition with risk management: Phase 1 (Weeks 1-2): Pick one non-brand Search campaign with at least 30 monthly conversions and stable CPA. Enable search term matching only. Monitor the search terms report daily. Add negatives aggressively for any irrelevant queries. Phase 2 (Weeks 3-4): If search term quality holds, enable text customization. Apply text guidelines - exclude terms that conflict with your brand voice, add messaging restrictions that anchor the AI's creative output. Review generated assets in your asset reports. Phase 3 (Weeks 5-6): If both features perform, enable Final URL Expansion. Set URL exclusions for pages you never want traffic directed to - blog posts, careers pages, privacy policies. Monitor the landing page report for any unexpected destinations. Phase 4 (Ongoing): When testing AI Max, assess the full account-wide impact. Don't rely on CPA by match type to assess AI Max's efficacy. What you really want to know is whether AI Max has improved your overall ability to generate returns at an incremental investment you're comfortable with.

One tactical point: in testing, Seer Interactive found AI Max can expand much more aggressively than expected. In a non-brand campaign promoting a specific line of business, AI Max began picking up terms related to entirely different lines of business. Tight negative keyword management isn't optional - it's the price of admission. The broader trajectory is unmistakable. AI Max is becoming Google's default recommendation for Search campaigns, and the pressure to adopt will grow throughout 2026. Advertisers who hold back will find themselves managing older campaign structures that receive less platform support, fewer updates, and eventually less reach.

The overlap between DSA, AI Max, and Performance Max creates obvious redundancy, and a formal DSA deprecation announcement is likely in the second half of 2026 with a 12-to-18-month migration window.

The advertisers who will win aren't the ones who adopt fastest or resist longest. They're the ones who test methodically, read their search term reports, and treat AI Max as what it is: a powerful expansion tool that still requires a human hand on the controls. Automation scales what already works. Make sure what you're scaling is worth scaling.