Google Consent Mode V2 Guide
Google made Consent Mode V2 mandatory for all advertisers in the EEA from March 2024. Without it, campaigns lose conversion modelling, remarketing audiences shrink, and Analytics data becomes incomplete. This guide covers everything you need to know — from Basic vs Advanced mode to step-by-step setup with FlexyConsent.
What Is Google Consent Mode V2?
Consent Mode V2 is Google's framework for adjusting how Google tags behave based on a visitor's consent status. When a user accepts or rejects cookies, your CMP communicates the decision to Google tags in real-time through four consent parameters.
Basic vs Advanced Mode
- Basic Mode: Google tags only fire after the user gives consent. No data is collected from users who reject. Simple, but you lose all conversion data from non-consenters.
- Advanced Mode: Google tags fire immediately in a restricted, cookieless mode. After consent, they switch to full tracking. Google's AI uses the restricted-mode signals to model conversions from non-consenters — recovering up to 70% of otherwise lost conversion data.
The Four Consent Parameters
- analytics_storage: Controls whether Google Analytics can store cookies
- ad_storage: Controls whether advertising cookies (Google Ads, Floodlight) can be set
- ad_user_data: Controls whether user data can be sent to Google for advertising purposes
- ad_personalization: Controls whether personalised advertising is enabled
FlexyConsent manages all four parameters automatically based on the visitor's consent choice.
Why March 2024 Changed Everything
Before March 2024, Consent Mode was optional. After the deadline, Google requires it for all EEA campaigns. Without it:
- Remarketing audiences stop growing — no new users are added to your audiences
- Conversion tracking becomes incomplete — 40-60% data loss depending on consent rates
- Smart Bidding degrades — algorithms cannot optimise without conversion data
- Customer acquisition costs rise — less data means less efficient campaigns
Step-by-Step Implementation
- Step 1: Add the FlexyConsent script to your site's <head> tag
- Step 2: Configure cookie categories in the FlexyConsent panel
- Step 3: Default consent state is set automatically (denied for EEA)
- Step 4: Google tags respond in real-time as visitors make consent choices
Common Mistakes to Avoid
- Using Basic when Advanced is available — you lose conversion modelling capabilities
- Not setting default consent state — tags fire without consent, violating GDPR
- Forgetting ad_user_data and ad_personalization — these two new parameters are required since March 2024
- Not testing after implementation — use Google Tag Assistant to verify consent state changes
FlexyConsent is a Google Certified CMP with native Consent Mode V2 support. Start free today.
Start Free Trial