Microsoft's AI Revenue Revealed for the First Time! OpenAI Contributes $24.1 Billion, Accounting for Over Half – Dependence Remains High

Newly disclosed filings from Microsoft (MSFT-US) reveal that the majority of the company's artificial intelligence (AI) revenue still stems from OpenAI, accounting for over half—and potentially close to 70%—of its actual AI revenue. This underscores the software giant's ongoing reliance on its partner.

In documents filed last week, Microsoft stated that revenue from OpenAI reached $24.1 billion during its fiscal year 2026, which ended in June this year. Microsoft's stock declined on Wednesday (5th), closing down 1.1% at $487.46 per share.

Microsoft CEO Satya Nadella previously announced during the third quarter of the fiscal year ending in March that the annualized run rate for AI-related revenue had already reached $37 billion. However, when Microsoft released its fourth-quarter fiscal 2026 earnings last week, it did not update the full-year AI revenue figure.

According to Bloomberg analysis, if we extrapolate from the 123% year-on-year growth in AI revenue that Microsoft reported in March, AI revenue for the fiscal year ending in June would be approximately $34 billion.

Based on this estimate, OpenAI's contribution of $24.1 billion represents over 50%—and possibly as high as 70%—of Microsoft's total AI revenue, confirming that OpenAI remains the primary source of income for Microsoft's AI business.

Under the partnership agreement, OpenAI pays Microsoft for AI computing resources, model development costs, and a portion of its revenue share. While Microsoft has been actively investing in Anthropic and developing its own AI models to reduce its reliance on OpenAI, investors continue to closely monitor how much of Microsoft's AI revenue still depends on OpenAI.

To date, Microsoft has publicly disclosed the overall scale of its AI business only twice: first in the quarter ending December 2024, when it announced that the annualized AI revenue run rate had exceeded $13 billion; second in the quarter ending March 2025 (fiscal Q3), when it reported the run rate had surpassed $37 billion.

A Microsoft spokesperson confirmed that the AI revenue figures include income from all AI customers, as well as service fees and revenue shares paid by OpenAI.

From the perspective of Microsoft's total revenue, however, OpenAI's significance diminishes. The company reported that recent quarterly new commercial bookings totaled approximately $51 billion, primarily driven by enterprise clients outside of AI startups. Nevertheless, in terms of year-over-year growth in new bookings, OpenAI remains the largest contributor.

Prior to this disclosure, Microsoft had never explicitly revealed the full revenue amount received from OpenAI. Olga Usvyatsky, founder of data analytics firm Nonlinear Analytics, suggested this disclosure might be related to OpenAI's preparations for an initial public offering (IPO).

The market is now focusing on another key question: within the $24.1 billion, how much comes from cloud computing and other services provided to OpenAI, versus revenue share derived from equity investment?

Jackson Ader, an analyst at KeyBanc, said: "If more of the revenue comes from providing services to OpenAI rather than investment gains, I would view this business more favorably."

According to Microsoft's earnings report released after markets closed last Wednesday, revenue growth in its Azure cloud business accelerated. CEO Satya Nadella also announced that the number of paying users for its AI assistant Copilot has exceeded 30 million, more than doubling from the previous quarter.

Rhind, CEO of GraniteShares, said these figures have convinced investors that Microsoft's massive capital expenditures on AI over recent years are finally generating returns. "The reason this rally has the potential to continue is because Microsoft has finally answered the question the market has been asking for the past 18 months: Will massive AI capital spending yield sufficient returns?"

Fueled by the positive earnings report, Microsoft's stock surged 24.9% cumulatively over last Thursday, Friday, and this Monday—the best three-day performance since October 2000—turning its year-to-date performance positive.