It’s now becoming mandatory to use Google Consent mode v2 from March 2024 if using remarketing and other ad personalisation features in Google products. This change is essentially being driven by the Digital Markets Act which has forced Google as a “gatekeeper” to ensure they have proper user consent for users of their products https://commission.europa.eu/strategy-and-policy/priorities-2019-2024/europe-fit-digital-age/digital-markets-act-ensuring-fair-and-open-digital-markets_en 

What is Consent Mode? 

Consent mode is a Google API which interacts with your website consent banner to define a user’s consent state. This consent state is used to determine if information about that user should be stored. For example, Google has the following “consent storage types” (as of Feb 2024). *The following descriptions are lifted from Google’s own support documentation.  

Consent Storage Types

  • ad_storage – Enables storage, such as cookies (web) or device identifiers (apps), related to advertising
  • ad_user_data – Sets consent for sending user data to Google for online advertising 
  • ad_personalization – Sets consent for personalized advertising 
  • analytics _storage – Enables storage, such as cookies (web) or device identifiers (apps), related to analytics, for example, visit duration
  • functionality_storage – Enables storage that supports the functionality of the website or app, for example, language settings.
  • personalization_storage – Enables storage related to personalization, for example, video recommendations. 
  • security _storage – Enables storage related to security such as authentication functionality, fraud prevention, and other user protection.

When you accept or deny consent to different consent types in your consent banner this choice interacts with the Consent Mode consent storage types to establish whether they are either “granted” or “denied”. This consent state is then sent as a parameter (gcs) with the related request to GA4 or Google Ads.

Google will then see this consent state (through the gcs parameter in the request) and update the data stored on their platform to fall in line with the consent the user has provided. 

Implementation Options

If a user does NOT consent to analytics and/or ad storage then Google tags will NOT send any data to Google’s servers. However, you will still need to implement consent mode to send the correct gcs parameter with the google requests. It’s important to note, the gcs parameter will also be “111” with this implementation i.e. analytics and ad storage has been consented to. As if this is not the case then the GA4 request would not be able to be made.

  1. Advanced Consent Mode V2 implementation 

Even when analytics and ad storage are set to “denied”, this method allows cookie-less pings to be sent to Google for modelling purposes. This allows businesses to get modelled data for non-consenting users and thus expected/extrapolated results for non-consenting users. This is a bit of a grey area, as far as compliance with data regulations is concerned, as you are still potentially sending personally identifiable information such as IP address, device etc. even though the user has explicitly stated they don’t want to be tracked. This seems to violate one of GDPRs core principles.

Pros and Cons

Implementation TypeAdvantagesDisadvantages
 

Basic

  • Safer, risk-averse strategy
  • Less potential legal advice needed to determine legality of approach
  • Acceptance of potential large amounts of data loss due to non-consenting users.
Advanced
  • Get modeled data for non-consenting users. Reducing potential data loss.
  • Potentially in breach of data regulations which carry significant penalties and fines.

Consent Management Platforms (CMPs)

Consent management platforms (CMPs) are implemented on your website to do the following:

List of CMP providers that integrate with GCM (lifted for the Google’s documentation – https://support.google.com/analytics/answer/9976101

Additional resources

What is consent mode v2?

https://www.simoahava.com/analytics/consent-mode-v2-google-tags/

https://support.google.com/analytics/answer/9976101?hl=en

How to implement it? https://developers.google.com/tag-platform/security/guides/consent?sjid=6028813699382652061-EU&consentmode=advanced#upgrade-consent-v2