OpenAI is finally ready to see if its users will trade their screen real estate for a free chat.

The AI giant announced Friday that it will begin testing ads within the Free and Go tiers of ChatGPT in the “coming weeks,” marking a watershed moment for the world’s most popular AI chatbot as it adopts a traditional monetization approach.

Ads will appear at the bottom of ChatGPT answers when there’s a relevant sponsored product or service tied to the ongoing conversation, the company said in a blog post.

The company said that ads will be “clearly labeled and separated from the organic answer,” and won’t appear for users under 18 or near “sensitive or regulated” topics such as health, mental health or politics. ChatGPT on the Plus, Pro, Business, and Enterprise plans will remain ad-free.