Understanding TCF 2.3 Updates

Didomi fully supports TCF 2.3 on both Web and Mobile.

For mobile integrations, make sure you are using Didomi SDK version 2.32.0 or higher to benefit from full TCF 2.3 compatibility.

Overview

The IAB Europe Transparency and Consent Framework (TCF) 2.3 introduces changes that impact how CMPs (Consent Management Platforms) handle TC Strings — particularly with the addition of a new disclosedVendors segment.

This article explains how Didomi’s CMP and SDK handle these updates, including requirements during the transition period and the creation and validation of TC Strings.

Click here to read the Didomi blog post for more information about TCF 2.3.

Rolling Out TCF 2.3

You can begin adopting TCF 2.3 ahead of the IAB’s official deadline. Depending on whether you are updating an existing notice or creating a new one, the rollout process differs slightly.

Rolling out TCF 2.3 on existing notices (before 28 February 2026)

You can switch an existing notice to TCF 2.3 at any time before the deadline directly from the Didomi Console:

Open the Didomi Console
Select the notice you want to update
Navigate to Customization → Integrations → IAB TCF
Select TCF 2.3
Publish your notice

Before publishing, make sure that all third-party vendors used on your website support TCF 2.3. If a vendor has not yet migrated, they may not be able to interpret the updated TC String correctly.

Newly created notices

Any created notice the Didomi console on or after November 26th, 2025 will have TCF 2.3 enabled by default.

After 28 February 2026

After the IAB’s enforcement date, Didomi will globally enforce TCF 2.3 on all notices.

This means all existing TCF notices will automatically switch to TCF 2.3, regardless of previous configuration.

TCF 2.3 updates

Disclosed Vendors Segment Compliance

Didomi’s SDK ensures that all vendors surfaced to the user are also included in the disclosedVendors segment when it is present in a TC String.

This guarantees alignment between what is shown in the user interface and what is recorded in the consent signal.

Vendors with Special Purposes Only

For vendors registered only for Special Purposes, the Didomi SDK continues to:

Set the Legitimate Interest (LI) bit to 1
Include these vendors in the CMP disclosure

This behavior remains unchanged from previous TCF versions and is still required under TCF 2.3.

User Interface and Resurfacing

You are not required to resurface the consent UI as part of this update.

Existing user choices remain valid, provided the TC String complies with the handling rules above.