Google Ads updated its Conversion Lift help documentation primarily to provide more detailed technical requirements and troubleshooting guidance for advertisers setting up incrementality studies. There are a lot of changes to the document but here are the big ones.
The Set up Conversion Lift based on users documentation updates include:
- Enhanced conversions: More detailed requirements around hashed customer data, email addresses, phone numbers, physical addresses, and transaction IDs.
- Offline conversions: Clarification that GCLID-only imports are insufficient; advertisers should use Enhanced Conversions for Leads with hashed first-party customer data.
- Unsupported setups: Explicitly identifies certain configurations, including GA4-imported web conversions, that aren't supported for Conversion Lift.
- Consent Mode: Adds more specific guidance around Advanced Consent Mode and measurement eligibility, particularly for EEA, UK, and DMA-related scenarios.
- App conversions: Adds more detailed requirements for Android, iOS, Firebase, and third-party app attribution integrations.
- Data quality: Recommends having 7–14 days of continuous conversion data before launching a study, passing dynamic conversion values and valid currencies, and routing approximately 75–80% of web conversion traffic through Google tag gateway.
Here is the old archived version if you want to compare, and here is a screenshot of the diff:
Overall, the update is more about strengthening measurement requirements than changing how Conversion Lift studies work. Google's existing recommendations around study duration, budgets, conversion thresholds, holdout sizes, bidding strategies, and campaign selection remain largely unchanged. The main takeaway for advertisers is to audit their conversion tracking setup before launching a study, especially if they rely on CRM/offline conversions, GA4 imports, or app conversions. Some reporting features, such as supplementary conversions and Demand Gen Cooldown, were already present in the archived version and aren't new additions.
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