Google Consent Mode v2, explained

What the four consent signals do, basic versus advanced mode, what happens to Google Ads and GA4 without it, and whether you need a certified banner.

Facts checked 30 October 2026. 6 minute read.

What it is

Consent Mode is a set of signals your cookie banner passes to Google’s tags. Before a visitor chooses, the signals say “denied”. When they choose, the banner updates them, and Google’s tags change what they collect to match. There are four:

Signal	What it controls
`ad_storage`	Whether Google can use cookies and identifiers for advertising.
`analytics_storage`	Whether Google Analytics can use cookies to measure visits.
`ad_user_data`	Whether data about the visitor can be sent to Google for advertising. New in v2.
`ad_personalization`	Whether the visitor can be shown personalised ads and added to remarketing lists. New in v2.

The last two arrived in November 2023, which is what “v2” means.

Do UK websites need it?

Yes, if you advertise with Google. Google’s EU user consent policy covers the UK, the European Economic Area and Switzerland, and ad_user_data is required for all three. If Google doesn’t receive the signals:

Remarketing lists get no data for those visitors, so you can’t retarget them.
Personalised ads are switched off for them.
Google can suspend personalisation, remarketing and conversion measurement for accounts that don’t follow the policy.

Google Analytics carries on counting visits without cookies when analytics_storage is denied, using cookieless pings and modelling to fill the gaps.

Basic and advanced mode

There are two ways to set it up.

Basic mode: Google’s tags don’t load until the visitor chooses. If they say no, nothing is sent to Google.
Advanced mode: Google’s tags load straight away with everything denied. They don’t set cookies, but they send cookieless pings, which Google uses to model the conversions and visits you’d otherwise miss.

Advanced mode recovers more data. In the UK, though, the cookie rules cover information read from a device, not just cookies, and the ICO hasn’t said whether advanced mode’s pings are allowed before consent. If you want to be cautious, use basic mode.

Do I need a Google-certified cookie banner?

Not for Consent Mode. Google lets you use any banner, or your own code, as long as it sends the signals correctly. Google requires a certified banner that supports the IAB Transparency and Consent Framework only if your site shows ads through AdSense, Ad Manager or AdMob.

How to check it’s working

Open Google Tag Manager and click Preview, then load your site.
In Tag Assistant, choose the Consent tab. Before you click anything in the banner, every signal should read “Denied”.
Accept or reject in your banner, and check the signals update to match.
Check that no Google Ads or Analytics cookies appear in your browser before you accept.

Sources

This guide explains the rules in general. It isn’t legal advice about your own website.