OpenAI on Friday announced it will begin testing ads within ChatGPT in the coming weeks, a highly anticipated decision that could kickstart a lucrative new revenue stream for the artificial intelligence startup.

OpenAI said its Plus, Pro and Enterprise subscriptions will not include ads, but it plans to start testing them with adult free users in the U.S. The company also made its low-cost Go offering available in the U.S. on Friday, and it said users who opt for that plan will also begin to see ads.

The company inked more than $1.4 trillion worth of infrastructure deals in 2025, and OpenAI CEO Sam Altman said in November that the startup was on track to generate $20 billion in annualized revenue run rate last year.

Introducing ads to ChatGPT could help OpenAI meet its ambitious spending commitments, as digital advertising has long been the cash cow for other big tech companies like Google and Meta.

Ads within ChatGPT will appear at the bottom of the chatbot's answers, and they will be clearly labeled, OpenAI said.

ChatGPT's responses will not be influenced by ads, and OpenAI said it will "never" sell users' data to advertisers, according to a release.

Users under the age of 18 will not see ads, and ads will not appear near certain topics, including politics, health and mental health, OpenAI said.

Altman has publicly expressed reservations about introducing ads to ChatGPT in recent years, stating in interviews that doing so could erode users' trust in OpenAI's products. But in a November podcast appearance, Altman said he expected OpenAI to try ads "at some point," though he added that he did not believe it would be the company's biggest revenue opportunity.

"We'll learn from feedback and refine how ads show up over time, but our commitment to putting users first and maintaining trust won't change," OpenAI said in a statement on Friday.

As OpenAI tests ads, the company said users will be able to learn more about why they're seeing a specific ads, dismiss ads and submit feedback about the experience.

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