Google Consent Mode v2 is a framework that allows your GA4 and Google Ads tags to adjust their behaviour based on the consent choices users make in your cookie consent tool. Required since March 2024 for advertisers who want to use audience-based features (Smart Bidding, Remarketing, Personalised Ads) for EU users in Google Ads, Consent Mode v2 is now a prerequisite, not an optional enhancement.
What Google Consent Mode v2 Does
When a user visits your website, Consent Mode communicates with your Google tags to tell them whether the user has consented to analytics and advertising cookies. Based on the signal received:
When a user consents: GA4 and Google Ads tags fire normally, setting cookies and collecting full data.
When a user declines: GA4 and Google Ads tags fire in “cookieless mode” — they do not place cookies, do not collect personal identifiers, but they do send aggregate pings that Google uses for modelling. Google uses these modelled signals to estimate conversion rates and audience composition for non-consenting users, partially restoring Smart Bidding effectiveness even without individual-level data.
Consent Mode v2 vs Consent Mode v1
Consent Mode v1 used two consent signals:
- analytics_storage: whether GA4 can use cookies
- ad_storage: whether Google Ads can use cookies
Consent Mode v2 adds two new required signals:
- ad_user_data: whether Google can collect and use user data for advertising purposes (required for Customer Match uploads, Enhanced Conversions)
- ad_personalization: whether Google can personalise ads (required for Remarketing audiences)
Without the v2 signals, Google cannot activate Remarketing or Customer Match audience features for EU users as of March 2024.
How to Implement Google Consent Mode v2 on Shopify
Option A: Through a CMP (Recommended)
Most major Consent Management Platforms (Cookiebot, OneTrust, Consentmo, Axeptio) have built-in Google Consent Mode v2 integration. When a user accepts or declines cookies in your CMP, the CMP automatically fires the appropriate consent signals to Google tags.
Setup: integrate your CMP with GTM or add the CMP script to your Shopify theme. Configure the CMP to send Consent Mode v2 signals. The CMP handles the rest.
Option B: Manual Implementation via GTM
If you are not using a CMP, you can implement Consent Mode v2 directly via GTM:
- Add a Consent Initialization trigger in GTM (fires before any tags, as early as possible)
- Create a Custom HTML tag that fires on the Consent Initialization trigger and sets default consent states: gtag('consent', 'default', { 'ad_storage': 'denied', 'analytics_storage': 'denied', 'ad_user_data': 'denied', 'ad_personalization': 'denied', 'wait_for_update': 2000 });
- Build or integrate a consent UI that fires an update when the user accepts: gtag('consent', 'update', { 'ad_storage': 'granted', 'analytics_storage': 'granted', 'ad_user_data': 'granted', 'ad_personalization': 'granted' });
The wait_for_update parameter (2000ms) tells Google tags to wait up to 2 seconds for a consent update before firing in denied mode. This prevents a race condition where the tag fires before the user’s saved consent preference is read.
What Happens to Your Data Without Consent Mode v2
Without Consent Mode v2 properly implemented for EU users:
- Google Smart Bidding cannot use modelled conversion data from non-consenting EU users — it bids based only on consenting users, which is an incomplete picture
- Google Remarketing audiences exclude non-consenting users (significant audience size reduction)
- Customer Match uploads will not work for EU users without ad_user_data: granted
- Google may serve a warning in your Google Ads account about missing consent signals
Verifying Consent Mode v2 Is Working
In Google Tag Manager Preview mode, check the Consent tab (available in GTM’s debug view). It shows the current state of all consent signals. Verify that:
- Default state: all signals show “denied” before the user interacts with the consent banner
- After accepting: all signals update to “granted”
- After declining: signals remain “denied”
Google Tag Assistant (the GTM Preview tool) also shows consent state in its tag details.
Get Your Consent Mode v2 Set Up Correctly
Consent Mode v2 is not complex to implement but requires careful configuration to ensure consent signals are sent before any Google tags fire. A misconfigured implementation can leave tags firing without proper consent signals, creating both compliance and performance issues.
Book your free Shopify tracking audit here and we will verify your Consent Mode v2 implementation is correctly configured and sending the right signals for all four consent parameters.