IAB Europe has released TCF v2.3. The key date to know is February 28, 2026: by then, all participants are required to fully support writing, reading, and processing the updated consent signal. After that date, any TC string that doesn’t include the required update will be considered non-compliant with the TCF.
If you use consentmanager by iubenda, TCF v2.3 is already supported and can be activated in your CMP. This article breaks down what changed compared to v2.2 and why it matters from an operational perspective.
What is the IAB TCF?
The IAB Transparency and Consent Framework (TCF) provides a standardized way to collect user choices and pass them through the ad tech ecosystem in a consistent format, known as the TC string.
This shared format is especially important in programmatic advertising, where multiple vendors rely on the same signal to understand whether and how they can process personal data.
The main change in v2.3: “Disclosed Vendors” becomes mandatory
The key update in TCF v2.3 is that the Disclosed Vendors section of the TC string is now mandatory.
IAB Europe explained that this change addresses the issue of vendors being unable to reliably determine, based on existing signals alone, whether they had actually been disclosed to the user in certain scenarios. This created uncertainties, particularly for vendors who rely on legitimate interest for special purposes.
With TCF v2.3:
- The Disclosed Vendors section must be present in all TC strings
- It must appear directly after the Core segment
- CMPs are expected to include it in all TC strings once the updated specification and reference implementation are released
What this means for consentmanager customers
consentmanager customers do not need to take any action, as the transition will take place automatically. Support for TCF v2.3 is already available in your consentmanager CMP dashboard. If you would like to activate TCF v2.3 before the deadline of February 28, 2026, go to “Menu” > “CMPs” > ‘Integrations’ > “IAB TCF” and change the setting from “2.2” to “2.3.” Alternatively, your CMP will be automatically updated at the end of February.
