Google Consent Mode v2 - what every site owner must know
Since March 2024 Google requires sites advertising to users in the European Economic Area to pass consent signals in the Consent Mode v2 standard. Without them Google Ads loses remarketing and GA4 loses a chunk of its data. Here is how it works and how to deploy Consent Mode without risk.
What is Consent Mode?
Consent Mode is the interface through which your site tells Google tags what the user has consented to. Instead of physically blocking Google scripts, it passes them the consent state, and the tags adapt on their own: without consent they set no advertising cookies and fall back to anonymous pings.
What is new in v2?
On top of the familiar ad_storage (advertising cookies) and analytics_storage (analytics cookies) signals, Google added two new ones:
ad_user_data- consent to sending user data to Google for advertising purposes,ad_personalization- consent to ad personalization (remarketing).
Without these two signals Google's advertising features in the EEA simply stop working for that user. This is not a matter of legal interpretation - it is a technical gate on Google's side.
The default state: denied
The key deployment rule: before any Google tag loads, the page must set the default consent state to denied. Only after the user's decision does the banner update the state with an update command. The reverse order (default after the tags) is the most common audit finding - data leaks in the window between the tag loading and the decision.
gtag('consent', 'default', { ad_storage: 'denied', analytics_storage: 'denied', ... })
...user decides...
gtag('consent', 'update', { ad_storage: 'granted', ... })
Basic or advanced mode?
- Basic - Google tags do not load at all until there is consent. Zero data before the decision, full compliance, the simplest audit.
- Advanced - tags load immediately but send only anonymous pings without consent (conversion modelling). More data for Google Ads, but it requires a careful legal assessment.
For most businesses we recommend basic mode: legally predictable and the easiest to defend during an inspection.
Deployment without manual configuration
Getting the signal order right (default denied before the tags, update after the decision) is the hardest part of the rollout. The CookieFox banner supports Consent Mode v2 natively: it sets the default denied state before any tag runs and updates all four signals according to the user's decision - no manual editing of gtag.js or Google Tag Manager. Create an account and verify it on your own site.
For the consent fundamentals, read our GDPR cookie consent guide.