Google Analytics has implemented several important changes throughout the past 9 years and to this day, that could influence how visitors are tracked, particularly concerning consent management and data collection practices.

These changes have strongly impacted the number of users tracked by website administrators, especially in the European area.

The following information synthesizes the best practices and industry updates related to Google Analytics, Consent Mode, and privacy requirements in 2025, as discussed in various announcements and documentations.

1. Stricter Enforcement of Consent Mode (Advanced Consent Mode Recommended)

• Google now strongly recommends implementing Advanced Consent Mode over the basic one. In Advanced Mode, Google tags load immediately but only send cookieless pings (including consent state and limited event data) if consent is denied. This allows for better modeling of missing data but could result in a lower number of users tracked directly if the consent/cookie banner is not compatible or configured correctly.
• If the cookie plugin in use does not integrate correctly with Consent Mode (e.g., it does not transmit granular consent signals for ad_storage and analytics_storage ), Google Analytics might rely heavily on modeled data instead of real user data, leading to a sharp perceived drop in tracking counts.

Sources:

• Consent Mode Overview: Google Support – About consent mode
  
• Site Kit documentation on consent: Site Kit by Google – Supported Services: Analytics

2. New Privacy Laws Requiring Explicit Consent

• Several new U.S. state privacy laws (e.g., Delaware, Iowa, Nebraska) and updated EU/UK regulations (e.g., DORA, Data Act) came into effect in 2025. These require websites to obtain explicit user consent before collecting data, especially for analytics and advertising.
• If your website has not updated its plugin or consent banner to comply with these laws (e.g., by allowing users to granularly disable analytical tracking), Google Analytics might fail to track users from regions with strict regulations, thus leading to a visible decrease in statistical data.

Sources:

• Italian decision on data transfer (an example of strict compliance): Garante per la protezione dei dati personali – Italian SA bans use of Google Analytics
• Analysis on the legality of GA in the EU: InfoTrust – The (Il)legality of Google Analytics: Italy’s Recent Response

3. Google Site Kit’s Default Consent Settings

• The Google Site Kit plugin for WordPress automatically enables Consent Mode for visitors from the EEA, Switzerland, and the UK. By default, these users are not counted in analytics until they explicitly grant consent. This could reduce tracked users if your website has significant traffic from these regions and a non-compliant or incorrectly set up cookie banner plugin.

Source:

• Official Site Kit documentation: Site Kit by Google – Supported Services: Analytics

4. Increased Use of Modeling for “Missing” Data

• Google Analytics now relies much more on AI-powered modeling to fill gaps where consent is denied. Although this provides estimated data, it might not faithfully reflect real user counts in reports. You might also see “(data not available)” values in traffic source reports when data is unavailable due to consent restrictions.
• Modeling requires a threshold of consented data to be accurate. If your website has low cookie consent rates, or they are not correctly managed by the cookie banner plugin, the modeled data could be even less reliable.

Source:

• Information on data collection and reporting in GA4: Google Support – [GA4] Overview of Google Analytics reports

5. Required Actions for Website Administrators

To ensure Google Analytics continues to track users effectively:

• Implement Consent Mode V2: Ensure your cookie banner integrates with Google Consent Mode and correctly sets the default and updated consent states for analytics_storage .
• Use a compliant consent banner: Replace faulty or non-compliant cookie plugins with a Consent Management Platform (CMP) that supports granular consent options and region-specific rules. Review settings regularly to avoid falling behind on legally updated configurations.
• Verify Site Kit settings: If you use Site Kit, review its consent and tracking settings (e.g., enable enhanced measurement) to avoid unintentional exclusion of statistical data.
• Audit data collection: Use Google Tag Assistant or diagnostic tools to check if consent signals are sent correctly and if tags fire as expected.

Sources:

• Site Kit settings and configuration: Google Support – Site Kit plugin (WordPress): Set up your Google tag
• Recommendations for a compliant implementation: Complianz – Italian Supervisory Authority denies use of Google Analytics

Conclusion

The incorrect management of user consent, through plugins and cookie services that are compliant and constantly updated, has led in recent years to a sharp decrease in tracked users on non-compliant websites. This is due to a combination of stricter consent requirements and changes in how Google handles data for which explicit user consent has not been obtained (e.g., from a compliant cookie banner).

To resolve any visitor tracking issues:

1. Fix the configuration or replace the cookie plugin in use if it is non-compliant, to ensure proper integration with Google Consent Mode.
2. Review Site Kit settings to ensure it is not excluding valuable traffic.
3. Monitor reports for “(data not available)” values and use Consent Mode diagnostics to identify problems.

Additional Sources:

• Official Consent Mode documentation: Supporto Google – Consent Mode
• Official Site Kit documentation: Site Kit by Google

For further details, refer to the official Google documentation on Consent Mode and Site Kit or get in touch with us.