Microsoft Earned $493.8M from OpenAI Last Year, $865.8M in First Three Quarters of 2025

On November 15, TechCrunch reported that after a year of trading frenzy and IPO rumors, OpenAI’s finances are under increased scrutiny.

Leaked files obtained by tech blogger Ed Zitron show Microsoft earned $493.8 million from OpenAI in 2024, rising to $865.8 million in the first three quarters of 2025. OpenAI reportedly shares 20% of its revenue with Microsoft, part of a deal tied to Microsoft’s $13 billion investment in the AI startup.

Meanwhile, Microsoft also returns about 20% of Bing and Azure OpenAI service revenue to OpenAI. Bing is powered by OpenAI technology, and Azure OpenAI provides cloud access to developers and enterprises. The leaked figures represent Microsoft’s net revenue share, excluding payments returned to OpenAI.

Based on the 20% revenue share, OpenAI’s 2024 revenue is estimated at least $2.5 billion, and $4.33 billion in the first three quarters of 2025. Altman recently projected OpenAI’s year-end annualized revenue run rate could exceed $20 billion, potentially reaching $100 billion by 2027.

On expenses, OpenAI spent about $3.8 billion on inference in 2024, increasing to $8.65 billion in the first nine months of 2025. Inference refers to computing resources required to run trained AI models. Historically, OpenAI has relied almost entirely on Microsoft Azure, but has recently partnered with AWS and Google Cloud.

These numbers suggest OpenAI’s inference costs may already exceed its revenue, raising questions about an AI bubble and potential ongoing losses.