Microsoft's Fiscal Q4 2026: Record Revenue, a $3.2 Billion Anthropic Windfall, and the $725 Billion AI Infrastructure Race

Full Fiscal Year FY2026: Record Highs

The fourth quarter capped a record fiscal year for Microsoft.

• Annual Revenue: Surpassed $331 billion, up 18% year-over-year — an all-time high for the company .
• Microsoft Cloud Annual Revenue: Exceeded $214 billion, up 27% .
• Azure Annual Revenue: Topped $100 billion for the first time, growing 41% for the full year .
• Operating Income: Grew 21% for the full year, to more than $155 billion .

Quarter vs. Full-Year: Q4 was Microsoft's strongest quarter of the fiscal year in both revenue ($90 billion quarterly versus approximately $241 billion across the prior three quarters combined) and EPS ($4.81 versus a year-to-date average of roughly $4.10). The Q4 net income figure of $35.8 billion is notably elevated by the one-time mark-to-market gains on AI investments . The stock jumped more than 8% in after-hours trading following the release .

Anthropic vs. OpenAI: A Tale of Two Investments

The quarter revealed a sharp divergence in the value of Microsoft's two most prominent AI equity stakes.

• Anthropic (Gain): Microsoft recorded a $3.2 billion unrealized gain on its investment in Anthropic, contributing roughly $0.33 to diluted EPS . This mark-to-market adjustment reflects Anthropic's rising valuation amid surging demand for its Claude models. Microsoft invested $5 billion in Anthropic in November 2025 as part of a circular agreement under which the AI lab also agreed to purchase $30 billion worth of Azure services .
• OpenAI (Write-down): Microsoft took approximately a $600 million impairment on its OpenAI stake during the quarter . While OpenAI has been the more visible partner through Microsoft's Copilot and Azure OpenAI Service, the write-down suggests a reassessment of its near-term valuation relative to Microsoft's carrying cost. Microsoft discusses its OpenAI investment quarterly but does not routinely mark its Anthropic investment to market .

Net effect: The $3.2 billion Anthropic gain more than offset the approximately $600 million OpenAI write-down, delivering a net positive swing of roughly $2.6 billion from AI equity investments in Q4 alone. According to Constellation Research, net income was boosted by a combined $2 billion from the two investments after accounting for the offset .

The Broader Context: An Unprecedented AI Infrastructure Buildout

Microsoft's Q4 results sit inside a much larger arms race among the largest hyperscale cloud providers. The four biggest US hyperscalers — Microsoft, Amazon, Alphabet (Google), and Meta — are collectively guiding to roughly $710–$725 billion in capital expenditure for calendar 2026, up about 77% from approximately $410 billion in 2025 . Adding Oracle pushes the total past $750 billion .

Per-company estimated 2026 capex:

• Amazon: Approximately $200 billion
• Microsoft: Approximately $190 billion
• Alphabet (Google): $175–$185 billion
• Meta: $115–$135 billion

What it's funding: The overwhelming majority of the increase is going to AI data-center infrastructure — GPU clusters, networking, new data-center builds, and power — to support frontier model training and inference at scale . Microsoft's approximately $190 billion spend represents roughly a doubling from about $95 billion in 2025 .

Microsoft's place in the race: Although Microsoft trails Amazon slightly in absolute capex, its spending is yielding strong results. Azure's 43% Q4 growth and the $100 billion-plus annual Azure milestone are the direct payoff from that investment. Management guided to continued double-digit revenue and operating-income growth in FY2027 .

Key tension: The massive combined spending figure is producing strong cloud revenue growth today, but investors are closely watching whether AI infrastructure returns will materialize as quickly as the spending is accelerating. Microsoft's Q4 — with its revenue beat, 32% EPS growth, and the $3.2 billion Anthropic gain — provided short-term validation, but the capex trajectory remains a central debate for the sector through the rest of 2026 .