Consent Mode v2, basic or advanced: what changes and how to check

What Consent Mode is, and isn’t

Consent Mode is a way to tell Google’s tags what your visitor chose. Google’s setup guide describes two commands: a default that sets each signal before anything else runs, and an update you send when the visitor interacts with your consent tool.

It does not collect the choice for you. Your banner does that, and the law behind it is still Article 5(3) of the ePrivacy Directive. Our post on whether you need a banner at all is here.

Basic vs advanced, side by side

Google’s consent mode overview (last updated 30 July 2026 when we read it) separates the two like this.

• Basic: Google tags are held back until the visitor interacts with the banner. If they decline, the tags don’t fire and Google receives nothing, not even the consent state.
• Advanced: Tags load when the page opens with the defaults you set (denied unless you configure otherwise). While consent is denied, they send measurements without cookies and with limited data. When consent is granted, they write cookies and send full measurement.
• Modelling: Google says advanced mode feeds a model specific to the advertiser, while basic mode relies on a more general one. Both depend on a data threshold, which Google Ads and Google Analytics document separately.

The trade-off in plain terms: advanced gives Google more to model from, but it means a request leaves the visitor’s browser before they have chosen. Whether that is acceptable under your national rules is a question for your lawyer or data protection authority. We haven’t found a regulator statement that settles it, so we don’t take a side here.

The four signals

• ad_storage: Advertising cookies. When denied, Google says no new advertising cookies are set.
• analytics_storage: Analytics cookies. When denied, analytics can run without them.
• ad_user_data: Whether user data can be sent to Google for advertising. New in v2.
• ad_personalization: Whether personalised advertising is allowed. New in v2.

Google’s guide says the last two were added in response to changes in its EEA consent enforcement, and that existing users should upgrade. A setup that only sets the first two is a v1 setup.

Three setup mistakes to look for

• The default loads late: Google’s guide says the default must run before the Google tag and before your consent tool, and that out-of-order calls mean the defaults won’t work. On a page with a tag manager, the default has to come first.
• A slow banner and no wait_for_update: If your banner loads asynchronously it can answer after the tags have started. The guide describes wait_for_update, a delay in milliseconds that holds tags until your tool sends an update. Its example uses 500.
• The choice isn’t remembered: Google says to persist the visitor’s choice, for example in a first-party cookie, so later pages can apply it. If the update never runs on the next page, you are back on the default. That is the reject not remembered problem.

A 5-minute check

Google’s debugging guide walks through this in Tag Assistant. In short:

• Open Tag Assistant and enter your URL. Before touching the banner, open the earliest Consent event and confirm all four signals were set in the default.
• Accept in the banner, then open the latest Consent event and confirm the same four were updated.
• On Tag Manager sites, open the Tags tab and click each tag to see whether it followed the consent settings.
• If you set region defaults, repeat with a simulated location.
• Now do the part Tag Assistant won’t do for you: reject everything, reload, and watch the network tab for analytics and ad requests. We haven’t found Google documentation that explains the gcs and gcd parameters in those requests, so treat them as hints and test behaviour instead.

Our Consent Mode v2 checker automates the first part, and the reject-all test covers the last. For the manual route, see the cookie banner check guide.

The most common failure is simple: Google tags that fire before the visitor chooses, covered in tracking before consent and tracking after reject. Selling online? The store test runs these checks alongside the rest of a shop’s list.

Choosing between them

If you want nothing sent to Google before a choice, basic is the closer fit, at the cost of less modelling. If you pick advanced, say in your privacy notice what is sent before consent. Whichever you choose, set it deliberately: Google’s guide says to follow your company’s guidelines for the method and the defaults.

This is general information from the documentation, not legal advice.