Google Consent Mode is an API that communicates the user's cookie consent choice to Google services (Analytics, Ads) through standard signals. Version 2 uses four signals: ad_storage, analytics_storage, ad_user_data and ad_personalization. When consent is not given, Google tags can send limited cookieless signals (in advanced mode) and missing data can be estimated through modeling.
Consent Mode passes the consent decision collected by the cookie banner to Google tags. Version 2 has four signals: ad_storage (advertising cookies), analytics_storage (analytics cookies), ad_user_data (sending user data for advertising) and ad_personalization (personalized advertising). In a correct setup, the default state starts as denied, and the relevant signals are updated when the user gives consent through the banner. Google requires v2 signals for sites using its advertising products in the European Economic Area and the UK.
There are two modes of operation. In basic mode, Google tags do not load at all until consent arrives; in advanced mode, tags send limited cookieless pings and Google can estimate missing conversions through modeling. Which mode is appropriate depends on your data policy and legal assessment. Crucially, Consent Mode is not a consent collection tool: a banner (CMP) that collects the consent is still required, and Consent Mode is only meaningful together with it. In practice, setup happens through CMP integration, where the banner translates the user's decision into Consent Mode signals via gtag or Google Tag Manager. After setup, it is good practice to verify that the signals are transmitted correctly using Google Tag Manager preview mode or the dataLayer entries in the browser console.
Frequently asked questions
Is Google Consent Mode v2 mandatory?
It is not a legal obligation but a policy requirement from Google: if you want to use Google advertising products (Ads, audience features, remarketing) for users in the European Economic Area and the UK, Google requires the v2 signals, including ad_user_data and ad_personalization, to be transmitted. Without them, ad measurement and personalization features are restricted. Your obligation to collect cookie consent comes from laws such as GDPR and KVKK and is independent of Consent Mode.
Does Consent Mode replace a cookie banner?
No. Consent Mode does not collect consent; it only passes an already collected consent decision to Google tags. A cookie banner (CMP) that presents choices to the user, records and documents the consent is still required. The correct architecture is: the banner collects consent, Consent Mode relays that decision to Google services as signals, and non-Google third-party scripts are separately blocked and loaded upon consent.
This content is for information only and is not legal advice.