Google Consent Mode v2

Google Consent Mode v2 — the mechanism Google uses to know whether a visitor has consented to tracking, and to fall back to "modeled conversions" when they haven't.

Six signals (v1) plus two added in v2:

• ad_storage — advertising cookies
• analytics_storage — GA4 cookies
• functionality_storage — preferences (e.g., language)
• personalization_storage — UX personalisation
• security_storage — fraud prevention (always granted)
• ad_user_data — v2 — sending data to Google for ad purposes
• ad_personalization — v2 — using data for personalised ads

The compliant pattern:

1. Set all signals to denied before any tag fires.
2. Update them when the visitor consents.

Google enforces v2 since March 2024 — without it, EU/EEA traffic stops accumulating remarketing audience signals. Stores typically lose 20–35% of "lost" conversions when they switch from blocking-only to GCM v2.

See also: GDPR, GTM.