Microsoft shares surged as much as 17% on Thursday to above $455, marking the largest single-day gain in nearly two decades. The rally followed the technology giant's fiscal year 2026 fourth-quarter earnings released on Wednesday, which appeared to reassure investors that CEO Satya Nadella and CFO Amy Hood's strategy for translating an estimated $190 billion in AI spending into accelerating revenue growth is delivering results.

Heading into earnings, Microsoft's stock had been down nearly 30% from its October 2025 peak of $555, weighed down by months of investor concern over uncertain returns in the AI sector amid a massive infrastructure buildout now projected to exceed $850 billion across hyperscalers and cloud providers combined. That spending has rippled across the entire AI supply chain, from chipmakers to power utilities, and scrutiny over whether it will generate commensurate revenue has been one of the defining tensions in technology investing over the past year. The stock had closed at $390.54 on Wednesday before briefly reaching $456 in afternoon trading on Thursday, adding approximately $483 billion in market capitalization over the session.

According to Jefferies, Thursday's rally represented the biggest one-day gain since 2008, when Microsoft shares rose 19%.

Earnings Beat Across the Board

The shift in sentiment followed fourth-quarter and full-year results in which nearly every metric surpassed analyst expectations, complemented by forward guidance that exceeded projections. Hood, who struck an notably optimistic tone during the earnings call, reported quarterly revenue of $90 billion—approximately $2.4 billion above the $87.6 billion consensus and up $13.6 billion, or 17.7%, year over year. Earnings per share reached $4.74, beating the consensus estimate of $4.24, while total quarterly net income stood at $35.8 billion.

Azure Crosses $100 Billion Threshold

Azure took center stage after Nadella provided Microsoft's annual update on the cloud platform's revenue. The company does not separately disclose Azure revenue, instead embedding it within its broader intelligent cloud segment. During the earnings call, Nadella announced that Azure surpassed $100 billion in revenue for the first time during fiscal year 2026.

William Blair analyst Jason Ader, who rates the stock as outperform, estimated fourth-quarter Azure revenue at $29.9 billion, up from $20.9 billion a year earlier. The 43% growth rate exceeded the company's own guidance range of 39% to 40%. Hood subsequently guided to 45% Azure growth for the next quarter ending in September, above the 41% analysts had anticipated, according to BNP Paribas.

For the full fiscal year 2026, Ader estimated Azure's revenue at $104 billion, compared with $75 billion the prior year.

OpenAI's $24.1 Billion Contribution

Microsoft's annual report disclosed that OpenAI accounted for $24.1 billion in fiscal 2026 revenue, with the AI company still owing Microsoft $6 billion in accounts receivable. OpenAI has been a focal point of concentration risk and a source of investor uncertainty, given the revenue-sharing arrangement with Microsoft and the degree to which Azure's growth has depended on the partnership.

Analyst research estimated that OpenAI was responsible for roughly half of Azure's $30 billion in year-over-year growth. Stifel's Brad Reback noted in his investment thesis that the relationship is becoming less competitively additive as Google closes the gap with Azure. Azure also continues to trail Amazon Web Services in the ongoing battle for customers and market share, making the diversification of Azure's revenue base a key consideration for investors assessing the durability of its growth trajectory.

However, BNP Paribas senior equity research analyst Stefan Slowinski estimated the $24.1 billion as approximately 23% of Azure's revenue, and indicated that Microsoft has a viable path to maintaining Azure growth above 40% as it introduces consumption-based pricing across its Copilot product lineup. Such metered pricing models, already standard in cloud infrastructure, broaden the addressable user base by allowing customers to pay based on usage rather than committing to fixed-seat licenses.

Slowinski, who maintains a $549 price target on Microsoft, wrote in a Thursday note that the quarter represented a turning point in the ongoing debate over Microsoft's revenue trajectory relative to its capital expenditures. He characterized the company as having reached an onramp toward revenue growth outpacing capex growth—an "equilibrium state" that investors had been seeking.

Broader AI Momentum and Analyst Reactions

Ader of William Blair described the quarter as one in which AI-driven momentum materialized across both Microsoft's application and infrastructure business lines. Stifel's Reback reported that Microsoft 365 Copilot seats surged to 30 million, a single-quarter increase of 10 million seats, well above investor expectations of approximately 6 million.

William Blair also pointed to commercial remaining performance obligations as a positive indicator, noting the increase to $678 billion from $368 billion a year ago—what Ader described as providing "tremendous demand visibility across enterprise and AI workloads." Commercial RPO represents contracted revenue not yet recognized, making it a widely watched forward indicator of future sales.

Reback, who carries a hold rating on Microsoft, raised his price target from $400 to $450. Stifel noted that Microsoft reported $55.4 billion in operating cash flow during the quarter, $6.7 billion above consensus.

Accounting Change to Affect Capex Reporting

Looking ahead, Microsoft announced a change in capital expenditure reporting that will make headline numbers more favorable and further enhance its free cash flow presentation. Hood guided to more than $50 billion in capex for the coming quarter, while simultaneously announcing an accounting change extending the estimated "useful life" of data center buildings to 25 years, up from the 15-year standard previously applied. Extending the depreciation timeline reduces the annual non-cash charge flowing through the income statement, mechanically lifting reported operating income and earnings per share without changing actual cash outlays.

The adjustment will reclassify certain future finance leases as operating leases, reducing Microsoft's reported capex figures. For example, even while maintaining 2026 spending plans of $190 billion, the new classification would permit reporting a figure of $175 billion.