Consent Mode v2 in GA4 - what you need to know
With Consent Mode v2 Google added two new signals: ad_user_data and
ad_personalization. Setting neither or setting them wrong risks
breaking audiences and personalization.
What changed
Before Consent Mode v2, ad_storage and analytics_storage were
sufficient. The two new signals now explicitly control whether a user can
be included in personalization and modelling.
How to do it right
- Set defaults BEFORE every
gtag('config', ...). - Update them as soon as the CMP decision is in - without page reload.
- Validate in the auditor's tracking debugger that both signals are sent.