Two ways to implement it
Google Consent Mode can be implemented in two ways, and the difference between them shows at exactly the moment a visitor declines.
In basic mode, Google tags do not load until the visitor interacts with the banner. If they decline, nothing is sent to Google, not even the consent state.
In advanced mode, tags load when the page opens, with a default consent state. While consent is denied, they send cookieless pings. Full data is sent only after the visitor accepts.
Basic mode
- Before the choice
- Google tags do not load.
- After a refusal
- Nothing is sent to Google.
- Modelling in Google Ads
- Based on a general model.
Advanced mode
- Before the choice
- Tags load, with the default state.
- After a refusal
- Cookieless pings are sent.
- Modelling in Google Ads
- Based on a model specific to the account.
What cookieless pings contain
When consent is denied, tags in advanced mode do not store cookies. According to Google, they send signals about the consent state and about activity, which contain:
- functional information: the time, the browser type and the referrer;
- general information: whether the page URL contains information about an ad click, the consent state, a random number generated on each page load, and the identifier of the consent platform.
Google Analytics uses these signals for modelling.
Conversion modelling in Google Ads
For conversions that cannot be observed directly, Google Ads uses modelling. In basic mode, the estimate is based on a general model. In advanced mode, Google builds a model specific to the advertising account, which it describes as more precise.
Modelling does not start automatically. To protect users, tags must reach a minimum threshold of collected data. Results on the impact of Consent Mode appear only after at least 7 full days from implementation, and only if the threshold is met.
Behavioural modelling in GA4
Google Analytics 4 can use machine learning to estimate the behaviour of visitors who decline analytics cookies, based on similar visitors who accept them. This makes it possible to estimate metrics such as the number of daily active users.
The conditions published by Google are:
- Consent Mode is active on all pages of the site.
- The property collects at least 1,000 events per day with
analytics_storagedenied, for at least 7 days. - The property has at least 1,000 users per day sending events with
analytics_storagegranted, on at least 7 of the past 28 days.
Meeting these conditions does not guarantee modelling. Google includes it in reports only when it has high confidence in the quality of the model. For a store with low traffic, the thresholds can be hard to reach, and reports then rely on observed data.
How to choose between the two modes
Basic mode is the simplest to explain to visitors: before consent, no Google tag runs. Advanced mode retains more information for modelling, but it also sends cookieless pings for visitors who have declined.
The difference therefore also depends on how the store interprets its obligations regarding personal data. The choice is worth discussing with whoever handles compliance for the store, not only with whoever manages the campaigns.
Key takeaways
- A refusal does not automatically mean the data is lost entirely. Depending on the implementation and the traffic volume, part of the activity can be estimated through modelling.
- Modelling depends on volume. In both Google Ads and GA4, Google applies minimum data thresholds.
- Signals must arrive on time. The default state is set before the tags, and the visitor’s choice is sent immediately after they make it.
On Shopify
Consentia sends all seven Consent Mode v2 signals, by category, before Google tags load on Shopify stores. Details are on the Google Consent Mode page.
Sources: Google, Consent Mode overview · Google Ads Help, About Consent Mode · Google Analytics Help, About behavioural modelling.