Google Consent Mode v2: A Guide for Website Owners

Google Consent Mode v2 (GCM v2) represents the latest evolution in Google’s system for managing user consent and data collection in line with European privacy regulations. Businesses had until March 6, 2024, to implement this update to remain in compliance, making it essential for website owners to understand its impact.

What is Google Consent Mode?

Google Consent Mode (GCM) allows websites to measure conversions and collect certain data while respecting user consent choices, specifically regarding cookies. When a user consents to cookies, data collection functions as usual, covering analytics, advertising, and other Google tools. 

However, when a user declines cookies, GCM adjusts data collection, gathering only anonymous data that supports basic functionality.

One of the standout features of GCM is its ability to use data modelling to estimate lost conversions for users who did not consent to cookies. This approximation helps businesses maintain some insight into user behaviour even when direct data isn’t available. 

Why is Google Consent Mode v2 Important?

Businesses that fail to adopt GCM v2 by the March 2024 deadline lose access to valuable data on users from the UK and EEA across Google platforms, including Google Ads and Google Analytics.

This potential loss of data comes with the following implications:

• Limited Remarketing
  Without the necessary data, remarketing to new users in the UK and EEA becomes impossible.
• Reduced Conversion Accuracy
  Google’s algorithms lose the ability to track and predict conversions accurately, impacting overall campaign performance.
• Optimisation Challenges
  With restricted data access, optimising Google Ads campaigns effectively becomes difficult.

Key Changes in Google Consent Mode v2

When GCM v1 was first launched it let you tell if people had provided consent to store analytics and advertising cookies in their browser. To do this we could set values for two parameters:

• analytics_storage
• ad_storage

GCM v2 introduces two additional parameters, enhancing how data collection aligns with user consent:

• ad_user_data
  Governs whether personal data is shared with Google for advertising. If a user consents to advertising cookies, this parameter is set to “granted.”
• ad_personalization
  Controls the use of personal data for personalization activities, like remarketing. It’s set to “granted” when users agree to personalised advertising cookies.

These parameters offer a more nuanced approach to consent, allowing businesses to tailor data collection according to user preferences.

Implementation of Google Consent Mode v2

Implementing GCM v2 requires adjustments to a website’s cookie policy and consent settings:

• Update Your Cookie Banner
  Ensure the language aligns with Google’s privacy standards, reflecting the new options for consent.
• Revise Your Privacy Policy
  Clearly outline how user consent is collected and what happens to the data based on their choices.

If your business uses a Google-certified Consent Management Platform (CMP), these updates may happen automatically. However, it’s a good idea to verify this with your CMP provider. For businesses without a Google-certified CMP, adding the ad_user_data and ad_personalization parameters through Google Tag Manager will be necessary.

Basic Consent Mode vs. Advanced Consent Mode

GCM v2 offers two implementation options that website owners should consider:

• Basic Consent Mode
  Implementing consent mode in its basic form ensures that Google tags remain inactive until a user interacts with the consent banner. This means no data is sent to Google before the user makes their choice. If consent is granted, the tags load and activate the consent mode APIs. If consent is denied, no data—including the user’s consent status—is transmitted to Google. The tags remain entirely blocked from firing. In such cases, Google Ads relies on a generalised conversion model to estimate performance.
• Advanced Consent Mode
  With the advanced version of consent mode, Google tags load immediately when a user visits your website or app. Upon loading, the tags initialize the consent mode API. Advanced implementation supports enhanced modelling by using advertiser-specific models rather than the general model applied in the basic version.

For most website owners, Advanced Consent Mode is recommended. Its ability to capture anonymous pings helps Google’s algorithms create more accurate estimates, leading to better optimisation of ads and a more complete understanding of user actions.

Closing Thoughts

Google Consent Mode v2 is a substantial upgrade, impacting how businesses handle user consent and data collection. Implementing GCM v2 not only ensures compliance with data privacy regulations but also mitigates negative impacts on marketing effectiveness. Although transitioning to GCM v2 may seem daunting, the benefits of compliance far outweigh the potential penalties and lost data.