Google Ads AI Max for eCommerce: Setup, Risks, and ROAS Protection

Question 1

What is Google Ads AI Max for Search?

Accepted Answer

According to the article, AI Max for Search is an opt-in, campaign-level layer on existing standard Search campaigns, not a new campaign type. It expands keyword matching beyond explicitly bid terms, dynamically generates headlines and descriptions in real time, and uses URL expansion to send traffic to indexed pages the system deems relevant. The article describes it as bringing Performance Max-style automation into the Search campaign format.

Question 2

How does URL expansion affect ROAS for product-heavy eCommerce sites?

Accepted Answer

The article states that when URL expansion is enabled, paid traffic can be sent to any page considered relevant, including blog posts, out-of-stock product pages, size guides, FAQ pages and return policy pages. For eCommerce, the article says ROAS erosion often begins when high-intent buyers are routed to non-purchase pages instead of product listing pages. To protect ROAS, the article recommends aggressive URL exclusion lists for blog directories and pages without an add-to-cart path, plus weekly review of the landing pages report.

Question 3

How should an eCommerce advertiser set up AI Max without hurting ROAS?

Accepted Answer

The article recommends auditing the site and building an exclusion list before enabling AI Max, then enabling it on a single campaign with stable historical performance to isolate impact. It recommends setting URL expansion to on with exclusions or off initially, and using value-based bidding such as target ROAS or maximize conversion value rather than maximize clicks or maximize conversions. It recommends monitoring search terms and landing pages daily for the first two weeks and pre-loading negative keyword lists for informational terms and adjacent categories.

Question 4

What conversion signals should I feed AI Max for best eCommerce results?

Accepted Answer

The article states AI Max should be optimized toward purchase conversions as the primary signal, not add-to-cart or page views, and every conversion should pass revenue values. Without revenue data, the article notes AI Max treats a $10 purchase the same as a $500 purchase. It also recommends implementing enhanced conversions and, where possible, passing margin-adjusted values, giving the example of a $100 product with 60% margin versus a $200 product with 15% margin.

Question 5

Should I run AI Max for Search alongside Shopping and Performance Max?

Accepted Answer

The article states AI Max applies to Search campaigns only and does not directly modify Shopping or Performance Max campaigns, but broadened Search reach can overlap with queries those campaigns already serve and create internal auction competition. The article recommends Performance Max for Shopping-heavy product coverage and cross-channel reach, AI Max-enabled Search for high-intent text coverage including branded, category and competitor terms, and standard Search without AI Max for the most critical highest-converting keywords. It notes Google does not provide a clean deduplication report, so search terms, landing pages and conversion data must be cross-referenced.