That means companies must now comply with the restrictions and can face penalties if they fail to do so.
The AI Act bans certain applications of AI which it deems as posing "unacceptable risk" to citizens.
Those include social scoring systems, real-time facial recognition and other forms of biometric identification that categorize people by race, sex life, sexual orientation and other attributes, and "manipulative" AI tools.
Companies face fines of as much as 35 million euros ($35.8 million) or 7% of their global annual revenues — whichever amount is higher — for breaches of the EU AI Act.