Consent Mode v2: basic vs advanced, and how to tell which one you have

Consent Mode tells Google tags what the visitor agreed to. In basic mode, Google tags do not load until the visitor accepts, so nothing is sent for people who decline. In advanced mode, tags load at once with consent denied and send cookieless pings, which gives Google more to model the conversions it cannot see.

Published 2026-10-27

What Consent Mode does

Your cookie banner collects the visitor's choice. Consent Mode passes that choice to Google tags, so they adjust what they store and send. Version 2 added two parameters that Google requires for ad personalisation and remarketing for visitors in the EEA and the UK. The parameters are:

ad_storage: advertising cookies.
analytics_storage: analytics cookies, such as the ones Google Analytics uses to recognise a returning visitor.
ad_user_data (v2): sending user data to Google for advertising.
ad_personalization (v2): using data for personalised advertising such as remarketing.

Each is set to denied by a default before tags fire, then updated to granted when the visitor accepts.

Basic vs advanced

	Basic	Advanced
Before the visitor answers	Google tags do not load	Google tags load with consent denied
Visitor declines	Nothing is sent to Google	Cookieless pings: consent state, that a conversion happened, no cookies
Conversion modelling in Google Ads	General model	Advertiser-specific model
GA4 behavioural modelling	Not eligible	Eligible above Google's traffic thresholds

Which one is right is a decision for you and your legal advice, not a technical one. Basic mode sends less; advanced mode recovers more of the conversions that consent hides. For GA4's behavioural modelling, Google currently requires tags that load before the banner, and at least 1,000 events per day with analytics denied and 1,000 daily users with analytics granted, on at least 7 of the last 28 days.

How to tell which mode your site runs

Open your site in a private window. Do not touch the banner.
Open the browser's developer tools, Network tab, and filter for collect.
No Google requests at all: basic mode, or tags blocked by the consent tool, which behaves the same.
Requests with a gcs parameter such as G100 (the two digits are ad_storage and analytics_storage, 0 for denied): advanced mode. A gcd parameter shows the v2 values were set.
Requests with G111 before you answered: the default is missing or says granted. That is the problem the scan reports as "Consent Mode default is not set".
Click reject all and reload: the values must stay denied.

The free Consent Mode checker does all of this in a real browser, accepting once and rejecting once, and shows what Google received each time.

Common mistakes

The default runs after the Google tag, so the first hit goes out without it.
The default only sets ad_storage and analytics_storage, not the two v2 parameters.
The banner never sends an update, so every visitor stays denied and conversions look like they collapsed.
Consent Mode is set on some templates (home, product) but not on checkout or confirmation pages.
Non-Google pixels are assumed to follow Consent Mode. They do not: Meta, TikTok and the rest need to be blocked by the consent tool or given their own consent signal.

Run the free scan: it loads your page in a real browser, accepts and rejects the banner, follows redirects with test click IDs and reports what every platform received.

Check your own site

Sources

Based on the platforms' public documentation; menus and names change, so check the linked pages if a step looks different.