What Consent Mode v2 does
Consent Mode passes the visitor's consent decision to Google tags. Version 2 added two parameters, ad_user_data and ad_personalization, alongside ad_storage and analytics_storage.
When consent is denied, tags adjust their behaviour, and Google can model the conversions it can't observe.
How many sites actually send it
From the Website Privacy Index (47,419 sites scored, crawled January to September 2026):
- 23,307 sites ran Google tags with no consent signal at all (49.2%).
- 2,108 sent a working Consent Mode v2 signal (4.4%).
Full breakdown: Consent Mode v2 adoption
Why it's a measurement problem, not only a compliance one
With no signal, there's no gap for Google to model, so reports look clean whether or not anyone is being counted. Read: Consent Mode Is A Measurement Problem Before It Is A Compliance One
Where it breaks
- The banner decides, nothing transmits. Read: Your Consent Banner Made A Decision. Did Anything Transmit It?
- Nobody owns the setting between the privacy team and the media team. Read: Nobody Owns The Wire Between Your Consent Banner And Your Ad Platform
- Google tag changes move initialization, and with it the order consent defaults load in. Read: Your Google Tag Is About To Become A Container and The Google Tag Migration Is A Consent Event, Not A Rename
- Other domains. Checkout and regional sites don't inherit the consent record. Read: Your Checkout Is on a Different Domain. Your Consent Record Did Not Follow It. and The Consent Gap on Your International Domains: Why the .mx Site Fails Where the .com Passes
How to test it
- Load the site fresh, before touching the banner, and check what fires.
- Decline, then check again.
- Confirm the default and update consent commands both reach Google tags.
Read: Your Consent Banner Passed Launch Day. That Was The Easy Test.
Related reading
- More Than Four In Ten Cookie Banners Do Not Block Anything
- Cookie Banner vs. Consent Tool: Why "We Have a Banner" Fails a 2026 Audit
This guide describes technical implementation and observed scan results. It is not legal advice and does not determine whether any site meets a legal requirement. Privacy and consent obligations depend on your jurisdiction and circumstances; confirm them with your counsel.