Changes in Google Consent Mode v2: A Comprehensive Overview

2024-02-23 | Article | Insights

The landscape of digital privacy and data protection has evolved significantly with the introduction of key legislative frameworks such as the ePrivacy Directive, General Data Protection Regulation (GDPR), and the more recent Digital Markets Act (DMA). For businesses operating in the European Economic Area (EEA), compliance with these regulations is critical, particularly concerning the processing of personal data and the crucial role of end-user consent.

Transition to Google CoMo V2

The Digital Markets Act, effective from March 2024, has brought several changes, especially for major players like Google, referred to as 'gatekeepers.' Notably, the responsibility for collecting user consent required for utilising core platform services now rests with these gatekeepers. As a response to these regulatory shifts and the growing emphasis on user privacy, Google has introduced Consent Mode Version 2 (CoMo V2).

Key Changes in Consent Mode V2

In its effort to align with the evolving legal landscape and address the heightened demand for user privacy, Google has rolled out Consent Mode V2. The primary distinction lies in the addition of two new consent states: ad_user_data and ad_personalization, representing the user's consent for Google's advertising purposes and ad personalization, respectively.

  • ad_user_data: This state indicates whether user data can be sent to Google for advertising purposes.
  • ad_personalization: This state controls the use of data for personalised ads, such as remarketing.

In contrast to ad_storage and analytics_storage, these flags do not directly affect the functioning of tags on the website. Instead, they serve as supplementary parameters transmitted with the pings to Google services.

CoMo V2: Advanced vs Basic Mode

Consent Mode V2 has an impact on the behaviour of Google tags, affecting platforms like Google Analytics 4, Google Marketing Platform, and Google Ads. This adjustment applies to both App and Web setups.

The new version of Consent Mode introduced two concepts:

  • Advanced CoMo: Consent Mode allowing anonymous pings being sent when users deny consent.
  • Basic CoMo: Consent Mode allowing data collection only if consent is granted. Until it is granted any data collection is prevented.

New Hit Parameters: gcs & gcd

In addition to the existing "Google Consent Status" (gcs) parameter, which can have values like G100, G110, G101, or G111, you can also use the parameter: "Google Consent Default" (gcd).

The format of the gcd parameter follows a specific structure:

11 <ad_storage> 1 <analytics_storage> 1 <ad_user_data> 1 <ad_personalization> 5

Here, the constant "11" at the beginning is followed by values for each parameter separated by "1", with the sequence concluding with the constant value "5". The lowercase letters denote different consent statuses, indicating whether consent is granted, denied, or missing, and specifying events related to default and/or update consent signals.

Common constellations include p, t, q, and r, with l representing a missing consent type, and m, u, n, and v being rather rare and indicating incomplete or faulty implementations.

This is the different status combinations (not documented yet from Google) and examples:

When Google CoMo V2 should be used

Basic Consent Mode is highly recommended for all Google related tags, especially if your operations cover the European Economic Area. (EEA)

If you are using Google’s advertising services, Consent Mode should be a must:

  • If you collect first-party user data, utilize the Google Ads user_id, or share Conversions from GA4 to Google Ads, it is needed to implement CoMo V2 and configure the ad_user_data flag.
  • If you gather data for remarketing through Google's advertising services, it is essential to implement CoMo V2 and configure the ad_personalization flag.

The choice between the advanced and the basic version will help a lot to model the non-consensual data much better.


Businesses in the EEA using Google Ads or GMP should adopt or upgrade to Consent Mode V2. This is crucial for precise conversion tracking and efficient optimization of ad spending. By integrating a cookie banner in line with Consent Mode V2, businesses can effectively convey consent signals to Google, ensuring compliance with changing regulations and protecting user privacy.

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