May 13, 2026 · 6 min read

Consent Mode v2: What Changed and How to Implement It

Google's Consent Mode v2 is mandatory for any business using Google Ads or Google Analytics to target users in the European Economic Area (EEA) and the United Kingdom. If your website does not transmit valid v2 consent signals, Google will not record conversions from unconsented users, and you will lose audience remarketing lists across Google Ads, Display & Video 360, and Search Ads 360. Here is a comprehensive breakdown of what changed, how behavioral modeling operates, and how to execute a clean implementation.

Key Takeaway: Consent Mode v2 adds two new consent parameters — ad_user_data and ad_personalization — specifically designed to comply with the EU Digital Markets Act (DMA). Without them, Google Ads conversion tracking and audience lists degrade significantly.

Consent Mode v1 vs v2: What Changed?

Consent Mode v1 (introduced in 2020) offered two core consent signals:

analytics_storage: Controls whether analytics cookies can be written or read.
ad_storage: Controls whether advertising cookies can be used for tracking.

Consent Mode v2 expands this framework by introducing two new explicit signals required for advertising attribution and targeting:

Consent Parameter	Purpose & Functionality	Default State (UK/EU)
`analytics_storage`	Controls cookie storage for GA4 analytics sessions	`denied`
`ad_storage`	Controls cookie storage for Google Ads & conversion tracking	`denied`
`ad_user_data`	Grants permission to send user data (email, phone, CRM ID) to Google for ads	`denied`
`ad_personalization`	Grants permission for remarketing and personalised Google Ads delivery	`denied`

Basic vs Advanced Consent Mode: Architectural Comparison

When deploying Consent Mode v2, you must choose between two operating models:

1. Basic Consent Mode

Google tags are blocked entirely from executing until the visitor clicks "Accept" on your consent banner. If the visitor ignores or rejects the banner, no network requests are dispatched to Google servers. While straightforward to verify, you lose 30–50% of traffic visibility and receive zero behavioral modeling.

2. Advanced Consent Mode

Google tags initialize immediately on page load with all consent parameters defaulted to 'denied'. Before consent is granted, tags dispatch cookieless, non-identifiable pings to Google. If the visitor grants consent, tags update in real time to full tracking mode. If consent is denied, cookieless pings allow GA4 and Google Ads to model missing conversions and traffic with high statistical accuracy.

Capability	Basic Consent Mode	Advanced Consent Mode
Tag Firing Before Consent	Completely Blocked	Fires with Cookieless Pings
GA4 Behavioral Modeling	No	Yes (Recovers 50–70% of lost session insights)
Google Ads Conversion Modeling	Limited	Full AI Attribution Modeling
Regulatory Suitability	Strict EU/French CNIL environments	UK ICO & broad European consensus

Step-by-Step Implementation via Google Tag Manager

To implement Consent Mode v2 properly, add the default consent initialization script in the <head> of your website above your Google Tag Manager container snippet:

<!-- 1. Default Consent State (Above GTM) -->
<script>
  window.dataLayer = window.dataLayer || [];
  function gtag(){dataLayer.push(arguments);}
  gtag('consent', 'default', {
    'ad_storage': 'denied',
    'analytics_storage': 'denied',
    'ad_user_data': 'denied',
    'ad_personalization': 'denied',
    'wait_for_update': 2000
  });
  gtag('set', 'ads_data_redaction', true);
  gtag('set', 'url_passthrough', true);
</script>

Verifying Consent Signals in Browser DevTools

To verify that Consent Mode v2 is functioning correctly, open the Network tab in your browser's Developer Tools and filter for collect?v=2 (GA4) or googleads:

Look for the gcs query parameter. The format is G1xy, where x represents Google Ads consent and y represents Analytics consent:
- G100 = Both Denied
- G110 = Ads Granted, Analytics Denied
- G101 = Ads Denied, Analytics Granted
- G111 = Both Granted
Look for the gcd parameter, which encodes all four v2 signals (ad_storage, analytics_storage, ad_user_data, ad_personalization) into an octet string.

Need help configuring or auditing Consent Mode v2 for your clients? North Digital implements bulletproof consent architectures for UK & European brands. Contact our tracking engineers today.