Google Ads Expands Self-Serve Conversion Lift to Search and Performance Max Campaigns

Google Ads has expanded its Conversion Lift feature to include Search and Performance Max campaigns, allowing eligible advertisers to conduct self-serve incrementality tests. As reported by Search Engine Land on October 7, 2026, this update enables businesses to run these tests independently without needing a Google representative present.

Previously, user-based Conversion Lift was only available in Display & Video 360 for audiences applied to Display, Video, Demand Gen, and App campaigns. The inclusion of Search and Performance Max represents a major change, as these two campaign types typically command the largest portion of advertiser budgets.

Distinguishing Incrementality from Attribution

While traditional attribution models distribute credit among various touchpoints, they do not verify if an ad campaign actually caused a sale or if the sale would have occurred regardless. Conversion Lift tests address this directly by measuring real behavioral change.

This distinction is particularly valuable for Performance Max campaigns, which run across multiple Google channels and are often underestimated by standard attribution models. A lift test compares the performance of an entire campaign against a control group that has not been exposed to the ads.

The resulting insights help advertisers optimize their spend. For instance, if a campaign has a high return on ad spend (ROAS) but demonstrates low lift, an advertiser might choose to reallocate budget to a campaign with a lower ROAS but a higher lift.

Eligibility Requirements

Self-serve access to the Conversion Lift testing tool is restricted to accounts that meet three specific requirements outlined in Google's help center:

• Observed Conversions: The campaign must have at least 1,000 observed conversions, excluding any conversions that use supplementary data.
• Minimum Budget: The campaign budget for the study must be at least $5,000.
• Conversion Actions: The account must have at least one active conversion action that is compatible with Conversion Lift.

Because of these criteria, small accounts—such as businesses generating only dozens of conversions per month—are unlikely to qualify for the self-serve tests.

How Holdout Studies Work

To perform a lift study, Google Ads splits target users into two segments: an active group that is exposed to the campaigns and a holdout group that is not. Advertisers can manually set the size of this holdout group between 1% and 50%.

Choosing the holdout size involves a clear trade-off:

• Larger Holdouts: A larger holdout group increases test accuracy but carries an opportunity cost, as a large portion of the audience is blocked from seeing the ads.
• Smaller Holdouts: A smaller holdout group reduces this opportunity cost but requires a longer study period to generate accurate, statistically reliable results.

Setting Up a Lift Study

Advertisers can configure and launch these studies directly within their Google Ads accounts. The setup process involves several steps:

1. Navigate to the Campaigns tab, click on Experiments, and select the Lift studies tab.
2. Create a new study and select Conversion Lift based on users.
3. Enter a study name, select the target campaigns, and define the goals.
4. Choose the study dates, holdback size, and metric focus.

Depending on the selected focus, the study will yield different metrics:

• Conversions Focus: Delivers data on incremental conversions and incremental cost per action (CPA).
• Conversion Value Focus: Delivers data on the incremental return on ad spend (ROAS).

During configuration, Google Ads displays a study power estimate ranging from 50% to 95%, which indicates how certain the final experimental results will be.