What is Google Consent Mode v2?
Google Consent Mode is a system that lets Google's tags adapt their behavior based on whether a visitor has given consent. Version 2 introduced two new parameters: ad_user_data (whether Google may use the user's data for advertising) and ad_personalization (whether ads may be personalized).
These are added to the existing analytics_storage and ad_storage parameters from version 1.
Why is Consent Mode v2 mandatory?
Since 6 March 2024 the following applies:
- Without Consent Mode v2, Google Ads is limited to non-personalized campaigns for EU and EEA traffic
- Conversion data from users who decline consent is not reported
- Remarketing lists are not built for users who do not consent
- Smart bidding algorithms optimize on incomplete data
In practice: if 60% of your visitors decline consent and you do not have Consent Mode v2, you miss up to 60% of your conversion data.
Basic vs Advanced Consent Mode
Basic Mode: Google tags are blocked completely for users who do not consent. It is easier to implement but gives no conversion modeling.
Advanced Mode: Google tags always load, but send limited data for users who do not consent. Google can then model conversions with machine learning. It gives better data and is recommended by Google.
The correct default settings
A critical detail: analytics_storage and ad_storage should be denied by default. Many implementations set them to granted by default, which is a GDPR violation that IMY can fine.
The right configuration in GTM:
- analytics_storage: denied (default)
- ad_storage: denied (default)
- ad_user_data: denied (default)
- ad_personalization: denied (default)
The values are updated to granted only when the visitor actively accepts in your cookie banner.
Which CMP should you use?
You need a Google-certified CMP (Consent Management Platform). The most common ones for Swedish sites are Cookiebot (now Usercentrics), OneTrust and CookieYes. All three support Consent Mode v2 and are Google-certified.
The CMP communicates the consent status to GTM, which in turn updates the Consent Mode parameters.
Frequently asked questions
Is Consent Mode v2 mandatory?
Since 6 March 2024 Google requires it from anyone advertising to EU and EEA users. Without it, Google Ads is limited to non-personalized campaigns for that traffic.
Basic or Advanced Mode?
Advanced Mode gives better data because Google can model conversions for users who decline, and Google recommends it. Basic Mode is simpler but gives no conversion modeling.
What should the default values be?
analytics_storage, ad_storage, ad_user_data and ad_personalization should all be denied by default and only updated to granted when the visitor actively accepts.