What Is Google’s Additional Consent Mode & How Does It Work?

As a publisher in today’s digital ecosystem, managing user consent isn’t just a regulatory necessity it’s a strategic advantage. With evolving laws like the GDPR and Digital Markets Act (DMA), tools like Google Consent Mode and Google’s Additional Consent Mode have become essential to remain compliant, build trust, and protect your revenue.

This blog will walk you through everything you need to know about Google’s Additional Consent Mode, its benefits, how it works, and how Mandatly CMP makes it simple to implement.

Google’s Additional Consent Mode is a privacy extension to the IAB Europe’s Transparency & Consent Framework (TCF) v2.2. It helps websites collect user consent for Google-approved Ad Tech Providers (ATPs) that are not part of the IAB TCF.

Unlike Google Consent Mode, which manages how Google’s own tags behave, Additional Consent Mode is specifically built to ensure consent for non-TCF vendors so they can legally and effectively serve personalized ads.

By gaining valid consent for a broader set of vendors, publishers can display more personalized ads, resulting in higher fill rates and better CPMs.

Google mandates that publishers using its ad services comply with its EU User Consent Policy. Without consent, only non-personalized ads (or no ads) can be served to EU users.

It does not replace the IAB TCF v2.2 process but works in parallel, adding coverage for Google-approved vendors that fall outside the standard framework.

Understanding the distinction is key:

Related Read: What Is Google Consent Mode v2?

The Additional Consent (AC) string is a piece of structured data generated by your CMP. It includes:

• A version number
• A list of ATPs the user has consented to
• A list of disclosed ATPs shown in your consent banner

The AC string is sent alongside the TCF string to inform ad tags of the user’s consent choices. Without it, consent for these extra vendors can’t be legally or technically communicated.

Google updated Additional Consent Mode with:

1. Expanded AC String Support – Now includes all vendors disclosed by the CMP.
2. Improved CMP API Integration – Better compatibility with other privacy and ad tech tools.

These changes reflect a shift toward greater transparency and a smoother experience for publishers and users alike.

Mandatly is a Google-certified Consent Management Platform (CMP) that fully supports Google’s Additional Consent Mode.

• Compliant by Design: Seamless adherence to global privacy regulations.
• Revenue-Boosting: Gain consent from more ad tech partners = more personalized ads.
• User Trust: Clear, transparent consent banners that align with best practices.

Mandatly makes consent management simple, scalable, and future-proof.

Google’s Additional Consent Mode ensures your monetization strategy remains strong while staying privacy-compliant in the EU and beyond. When combined with a trusted CMP like Mandatly, publishers can confidently manage complex consent needs without sacrificing ad performance.

Maximize your ad revenue, protect user privacy, and stay ahead of compliance regulations all in one platform.