Google Consent Mode explained

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An overview of Google Consent Mode, the four key benefits of using it across Google products and how it impacts the migration to Google Analytics 4.

Four years after GDPR regulations came into effect, data privacy continues to shape the future direction of the internet. The phase-out of third-party cookies is one of the biggest changes taking place across the industry right now, shaping everything from the future of advertising and analytics, as seen with the rollout of Google Analytics 4 (GA4).

In 2020, Google launched Consent Mode for its analytics and advertising systems to simplify consent and data management. The tool makes it easier to capture, record and comply with users’ consent choices. Crucially, it allows you to collect non-identifying data – even when users opt out – instead of losing 100% of the data while adhering to GDPR and other privacy guidelines.

What is Google Consent Mode?

Consent Mode is a cross-platform consent system that allows you to adjust how tags in Google Analytics, Google Ads, etc. behave, based on the consent choices of users. The tool first launched in September 2020 to help website owners handle the challenges of managing data consent post-GDPR.

Now, the tool is an instrumental part of the search giant’s plans for moving away from third-party cookies.

Consent management consists of three key requirements:

  1. Allowing your users to deny or grant consent for storing information about their behaviour.
  2. Communicating those consent choices to the measurement system.
  3. Ensuring that Google and third-party tags comply with users’ consent choices.

Typically, websites use software tools called Consent Management Platforms (CMPs) to handle requirements 1 and 2. This usually involves some kind of a popup requesting consent from the user with several options and information about the types of tracking being used.

Consent Mode is designed to handle the third requirement by ensuring Google and third-party tags comply with users’ consent choices.

The following Google services currently support Consent Mode:

  • Google Analytics
  • Google Ads (Google Ads Conversion Tracking and Remarketing)
  • Floodlight (conversion tracking system for Google Marketing Platform (360))
  • Conversion Linker

Consent Mode is an API that allows all of these services to operate based on user consent settings. Users can choose their consent options for each service independently and Google consent will store this information for future sessions.

So, if users opt in for certain settings on your website for Google Analytics but refuse certain settings for Google Ads, these options are stored and respected across future sessions without any interruption to your data collection or issues with privacy guidelines, such as GDPR.

Currently, there are five tags that support Consent Mode:

  1. ad_storage: Enables storage (such as cookies) related to advertising.
  2. analytics_storage: Enables storage (such as cookies) related to analytics e.g. visit duration.
  3. functionality_storage: Enables storage that supports the functionality of the website or app e.g. language settings.
  4. personalization_storage: Enables storage related to personalization e.g. video recommendations.
  5. security_storage: Enables storage related to security such as authentication functionality, fraud prevention, and other user protection.

Even in instances where users opt out of all consent options, Consent Mode allows you to collect non-identifying data, which is protected by GDPR and other privacy guidelines. This means you’re not missing out on all user data, which is often the case with many cookie compliance solutions.

In 2021, Google introduced conversion modelling in Consent Mode that helps to fill in the data gaps when users opt out of consent options.

How this impacts migrating to Google Analytics 4

The latest version of Google Analytics moves away from its reliance on third-party cookies. With Google sunsetting Universal Analytics (UA) from mid-2023, companies are running out of time to migrate over to the GA4 but this isn’t the kind of migration where you can simply move all of your UA data over to the new system.

Google Analytics 4 uses an entirely different measurement model based on events, which replaces the old session-based model.

This means the majority of your data from Universal Analytics isn’t compatible with Google Analytics 4 and you have to start collecting data from scratch with GA4. One of the reasons for this incompatibility is the data-collection system used in previous versions of Google Analytics is problematic with modern privacy guidelines and overly reliant on third-party cookies.

Google Analytics 4 has an entirely new system for collecting and tagging data that adheres to privacy guidelines, including GDPR, and allows the system to operate without the use of third-party cookies.

Consent Mode is Google’s solution for gaining consent from users across its products, including Google Analytics and Google Ads, while still allowing you to collect as much data as possible without violating privacy regulations or users’ consent choices.

Using Google Consent Mode ensures that you receive vital insights and analytics through conversion modelling and non-identifying data, even when users choose to opt out of cookies.

Why use Google Consent Mode?

There are four key benefits to using Consent Mode across Google products:

  1. Adhere to privacy regulations, including GDPR
  2. Fill in the gaps of unconsented users
  3. Measure conversions while respecting user consent choices
  4. Manage consent across Google Analytics and Google Ads

Let’s explain these reasons in a little more detail.

#1: Adhere to privacy regulations, including GDPR

The most important benefit to using Consent Mode is that it helps you adhere to privacy regulations, including GDPR, while still being able to track whatever data remains available to you on platforms like Google Analytics and Google Ads.

Using Google’s Consent Mode meets privacy/GDPR compliance whilst still allowing some data to flow into your Analytics and Google Ads, rather than cutting it off almost completely which is what we are seeing with basic cookie control plugins, as it uses “cookieless pings” instead, which transmit non-identifiable data.

The key advantage of using Consent Mode with a compatible Consent Management Platform (CMP) in Google Analytics 4 is that you’re still able to transfer non-personally identifiable data between products, which avoids the data loss you get with a lot of cookie compliance plugins.

#2: Fill in the data gaps of unconsented users

Privacy regulations and the move away from third-party cookies centre around the use of data that can be used to identify individual users. This is called identifying data and includes any data point that can or could be used to identify individual people, such as location data that includes specific postal addresses or IP addresses.

For example, a user’s location in a public setting by itself couldn’t be used to identify them individually but combining this location with an IP address can.

Privacy regulations are designed to prevent data collectors from accessing this level of data from individuals without their explicit consent to their data being collected and used in the way collectors describe.

Consent Mode allows companies to collect non-identifying data when users opt out of consent for systems like Google Analytics and Google Ads. So, instead of missing out on all of the data in instances where users refuse to give consent, you still have the non-identifying data to work with.

Not only that but Google uses artificial intelligence and non-identifying data to fill in more of the gaps left behind by opt-outs.

#3: Measure conversions while respecting user consent choices

In September 2020, Senior Product Manager for Google Tag Manager, Scott Herman, introduced Consent Mode as a tool for measuring conversions while respecting user consent choices in Google Ads and Google Analytics.

“If a user consents, conversion measurement reporting continues normally. If a user does not consent, the relevant Google tags will adjust accordingly and not use ads cookies, instead measuring conversions at a more aggregate level.”

This allows you to continue attributing conversions to the right campaign and optimise for performance, even if users opt out of consent.

Google consent mode process

In April 2021, Google took this technology even further by introducing conversion modelling for consent mode. The system uses machine learning and intelligent modelling to fill in the gaps in conversion reporting by users who opt out of consent.

“Conversion modeling uses machine learning to analyze observable data and historical trends, quantifying the relationship between consented and unconsented users. Then, using observable user journeys where users have consented to cookie usage, our models will assess attribution paths for the unconsented journeys. This creates a more complete and accurate view of advertising spend and outcomes — all while respecting user consent choices.”

Based on its analysis, Google says that consented users are typically 2-5x more likely to convert than unconsented users with variations depending on consent rates, conversion types, industry and a range of other factors.

Google says that consented users are typically 2-5x more likely to convert than unconsented users with variations depending on consent rates, conversion types, industry and a range of other factors.

Google uses these insights to calculate the likelihood of unconsented users converting in each instance and reports this as an estimated figure for you.

#4: Manage consent across Google Analytics & Google Ads

Consent Mode makes it easy to manage consent across Google Analytics, Google Ads and other Google products.

Here’s a quick reminder of the five tags currently supported by Consent Mode:

  1. ad_storage: Enables storage (such as cookies) related to advertising.
  2. analytics_storage: Enables storage (such as cookies) related to analytics e.g. visit duration.
  3. functionality_storage: Enables storage that supports the functionality of the website or app e.g. language settings.
  4. personalization_storage: Enables storage related to personalization e.g. video recommendations.
  5. security_storage: Enables storage related to security such as authentication functionality, fraud prevention, and other user protection.

Consent mode provides a single system that respects user consent choices while maximising data visibility, regardless of which options they choose. In the worst-case scenario, users refuse to give consent for all settings and you rely on non-identifying data and Google’s intelligent predictions for reporting.

Obviously, the best-case scenario is that users provide consent for all requests but many users may provide consent for some and not for others, especially across different sessions. For example, you may find the same user refuses consent during their first visit when they click through from an ad – so they’ve opted out of Google Ads tracking.

However, the same user might later give consent for Google Analytics tracking when they visit your website from organic search.

As Senior Product Manager for Google Tag Manager, Scott Herman, explains:

“For example, if a user does not provide consent for ads cookies (and therefore advertising purposes are disabled), but does provide consent for analytics cookies, advertisers will still be able to measure site behaviour and conversions in Analytics as the “analytics_storage” setting will be enabled.”

With Consent Mode, you have a system that seamlessly collects, stores and respects these settings across the relevant platforms, regardless of which combined settings users define.

Do I have to use Consent Mode in Google Analytics 4?

Google requires you to obtain the correct consents from users in order to use their tools – you don’t necessarily have to use their Consent Mode mechanism to do this, but a similar process is required. Also, it’s important that you (and the data controller at your company) are aware that neither Google nor ourselves here at Vertical Leap are authorities on GDPR, other data privacy regulations or even the suitability of Consent Mode as a solution.

Like many tech companies, Google is working hard to create solutions that strike a balance between respecting data privacy and maximising reasonable data visibility for marketers and advertisers.

Google’s ongoing tug-of-war over implementing a new tracking system to replace third-party cookies illustrates how the search giant can run into problems with this.

You can read our post on Google replacing its previous FLoC proposal with the new Topics API for more details on this.

That being said, Google Consent Mode enhances the compliance of Consent Management Platforms (CMP) so widely used by websites post-GDPR. So, if there are any legal holes in Google’s technology, it’s still an improvement upon using most CMPs without Consent Mode or a similar solution.

On this basis, we do recommend using Google Consent Mode alongside a Consent Management System that supports the tool or the Interactive Advertising Bureau (IAB)’s Transparency & Consent Framework (TCF), which is now v2.0.

We can assist you with the implementation of a suitable CMP, Google Consent Mode and your migration over to Google Analytics 4 but we are not able to legally advise you on whether this is the best solution.

So, speak to the data controller for your company before implementing any data management system and seek relevant legal advice whether necessary.

Need help?

If you need any help with migrating over to Google Analytics 4 or further information on using Consent Mode, our analytics team can help. Call us on 023 9283 0281 to speak to our team today or fill out the contact form below and we’ll get back to you.

Kerry Dye profile picture
Kerry Dye

Kerry has been working in digital marketing almost since the beginning of the World Wide Web, designing her first website in 1995 and moving fully into the industry in 1996 to work for one of the very first web design companies. After a successful four years, Kerry moved to an in-house position for a sailing company, running the digital presence of their yacht races including SEO, PPC and email marketing as the primary channels. A stint then followed at another in-house role as online marketing manager. Kerry moved to Vertical Leap in 2007, making her one of the company’s longest-serving employees. As a T-shaped marketer – able to advise on digital strategy outside her main specialism – she rose through the ranks and in 2012 became the head of the Small and Medium Business (SMB) SEO team. In 2022 she became Vertical Leap's Automation and Process Manager. Kerry lives in the historic town of Bishops Waltham with her husband and daughter. When she’s not at work she enjoys cooking proper food, curling up with a good book and being a leader for Brownie and Rainbow Guides.

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