What Google Consent Mode does

Consent Mode works through consent “signals” that your CMP sets based on the visitor’s choice. Google tags read those signals and change behavior. The core signals are analytics_storage and ad_storage, which govern analytics and advertising cookies. Consent Mode v2 added two more, ad_user_data and ad_personalization, which say whether user data may be sent to Google for advertising and whether it may be used for personalization.

Google requires the two newer signals for EEA traffic used for ad personalization and measurement, with Customer Match enforcement from March 2024. This is Google’s own policy, separate from EU law.

Basic vs advanced Consent Mode

There are two ways to implement it, and they behave differently when a visitor declines.

Basic Consent Mode holds Google tags back entirely until the visitor consents. If they decline, the tags do not load and nothing is sent. This is the more conservative option and the closer fit to a strict consent-before-firing posture.

Advanced Consent Mode loads Google tags in a limited state even when consent is denied. They send “cookieless pings,” which carry no cookies or identifiers, and Google uses those to model conversions that were not directly measured. When consent is granted, full data flows. Advanced recovers more measurement, at the cost of sending some signal before consent, so whether it fits depends on your risk posture and how your regulator views cookieless pings.

Does Consent Mode make you compliant?

No. Consent Mode is a plumbing layer, not a compliance control. It only relays a choice that a compliant CMP has to collect, and it is only as good as the signals it is fed. Two failures are common: the CMP is set up but the consent signal never reaches Google’s tags, so they behave as if consent was given, or advanced mode is sending pings that a site assumed were fully blocked. Neither is visible without checking what the tags actually do.

How to verify Consent Mode is working

The test is whether Google’s tags behave the way the visitor’s choice says they should. DataTrue loads your site in a real browser, in each consent state, and records what the Google tags send. You can confirm that when a visitor declines, the tags respect it, that the consent signals actually reflect the banner choice rather than defaulting to granted, and, if you run advanced mode, exactly what the cookieless pings contain. The result is proof that the choice a visitor makes is the behavior Google’s tags follow.