Google Consent Mode v2 explained

What is Google Consent Mode v2?

Google Consent Mode is a link between your cookie banner and Google's tags, such as Google Ads, Google Analytics 4 and Floodlight. Your banner tells Google what the visitor chose, and the tags adjust their behavior: with consent they work as normal, without consent they do not use cookies or identifiers for advertising or analytics.

Google added two new signals in November 2023, which is why people speak of "v2". The two new signals cover whether user data may be sent to Google for advertising, and whether ads may be personalized. Google uses them to enforce its EU user consent policy, which applies to users in the European Economic Area, the UK and Switzerland.

Who needs it?

You need Consent Mode v2 if you have visitors from the EEA (the EU plus Iceland, Liechtenstein and Norway), the UK or Switzerland, and you:

• advertise with Google Ads and measure conversions or use remarketing;
• use Google Analytics 4 and share its data or audiences with Google Ads;
• use Floodlight or other Google Marketing Platform tags.

Since March 2024, Google only builds remarketing audiences and uses ad measurement for EEA users if it receives valid consent signals. Without them, those visitors drop out of your audiences and much of your conversion data disappears.

If you use no Google service for advertising or statistics at all, you don't need it.

The four signals

Google also knows three optional signals (functionality_storage, personalization_storage and security_storage), but the four above are the ones Google checks.

Before the visitor makes a choice, all four should be set to "denied". Only after consent does a signal switch to "granted" for that category. This default must be set before any Google tag loads; otherwise a tag may read cookies before it knows the visitor's choice.

Basic or advanced mode?

• Basic mode: Google's tags are blocked until the visitor interacts with the banner. If the visitor declines, nothing is sent to Google, not even the consent status. Google fills the gap with a general conversion model.
• Advanced mode: the tags load straight away with consent set to "denied". Without consent they send cookieless pings to Google, which Google uses for a more detailed, advertiser-specific model of the missing conversions.

Advanced mode gives you better measurement, but data is sent to Google even when the visitor declines. Whether that is allowed without consent is not settled. In its 2024 guidelines on the technical scope of the ePrivacy Directive, the EDPB says that instructing a visitor's browser to send information, for example through pixels or scripts, can fall under the cookie rule even when no cookie is set. If in doubt, choose basic mode.

And IAB TCF?

Google Consent Mode v2 is not the same as the IAB Transparency & Consent Framework (TCF). Consent Mode is what you need when you advertise with Google Ads or measure with Google Analytics. TCF is only required when you show ads from others on your own site, for example via Google AdSense. More in IAB TCF: who needs it?

How to set it up

1. Use a cookie banner that supports Consent Mode v2. It sets the default to "denied" before Google's tags load and updates the signals after the visitor chooses.
2. Map your categories: statistics to analytics_storage; marketing to ad_storage, ad_user_data and ad_personalization.
3. Using Google Tag Manager? Load the banner first, on the Consent Initialization trigger, and set your Google tags to respect the consent state.
4. Choose basic or advanced mode (see above).
5. Use geographic rules if you need them: you can default to "denied" only in regions where consent is required, but make sure every signal follows the same rule.

How to check it

Open your website with Google Tag Assistant and:

• select the first Consent event and check that all four signals have a default of denied;
• accept in your banner and check that the update switches them to granted; reject and check that they stay denied;
• look at the Tags tab to see which tags fired and which were held back.

An empty Consent tab usually means Consent Mode isn't on the page. The message that a tag read the consent state before a default was set means your banner loads too late. In Google Ads, the consent status can take up to 48 hours to appear.

With Cookie Confirm, steps 1 to 3 and 5 are handled for you: the banner sets the defaults, maps your categories to all four signals, applies geographic rules per country and works with our Google Tag Manager template. Rather not do it yourself? Our free Setup Service makes your site compliant within 24 hours after you give us access.

Sources

• Google: Consent mode overview
• Google Ads Help: Updates to consent mode for traffic in the EEA
• Google Ads Help: Consent mode reference
• Google Analytics Help: Verify and update consent settings
• Google: Troubleshoot consent mode with Tag Assistant
• Google: EU user consent policy
• EDPB: Guidelines 2/2023 on the technical scope of Art. 5(3) ePrivacy Directive