The Big Picture: Revenue Race Remains Tight
On the surface, both behemoths delivered another quarter of staggering growth. For its fiscal fourth quarter ending in June, Microsoft is expected to report revenue around $87.6 billion, continuing its strong performance. Amazon, reporting its second
quarter, is anticipated to post revenues near $196 billion. While Amazon's total sales number is much larger due to its massive retail operation, the overall growth story for both companies in their most recent reported quarters was remarkably similar, with Microsoft's revenue growing 18% and Amazon's 17%. But the headline numbers only tell part of the story. The real drama is unfolding in the cloud, where the race to dominate the AI era is being fought.
The Cloud Battlefield: Azure's Growth vs. AWS's Scale
For years, Microsoft’s Azure has been the faster-growing challenger to Amazon Web Services (AWS), the established market leader. Recent results show this trend continuing. In its most recent reported quarter (Q3 FY26), Microsoft's Azure and other cloud services revenue surged by a blistering 40%. In contrast, AWS grew 28% in its last reported quarter, a figure that was still its fastest pace in nearly four years. Analysts expect AWS growth to re-accelerate to between 32% and 35% in the just-closed quarter, but Azure is still setting a furious pace. The key difference is scale. AWS remains the larger overall service, generating the bulk of Amazon's profits. It accounted for nearly 60% of Amazon’s operating profit in the first quarter of 2026. Microsoft's Intelligent Cloud segment, which houses Azure, has now grown to be nearly equal in size to its legacy Productivity and Business Processes segment for the first time, highlighting its central importance.
The Margin Squeeze: AI's Staggering Price Tag
This is where the story gets complicated. The AI revolution isn't cheap, and both companies are spending at a scale that has investors on edge. Amazon and Microsoft are projected to spend a combined total approaching $400 billion on capital expenditures (capex) in 2026 alone, with most of it dedicated to building out AI data centers. This unprecedented spending is putting pressure on profit margins. An operating margin shows how much profit a company makes from its core business operations. In its first quarter, AWS posted a robust operating margin of 37.7%. Analyst consensus for the second quarter pegs the AWS margin around 33.8%, reflecting the impact of these heavy investments. Microsoft has also warned that elevated investments in data centers are modestly pressuring its cloud margins in the near term. The central question for Wall Street is whether the massive spending on AI infrastructure will translate into higher profits quickly enough to justify the cost.
Looking Ahead: It’s All About Future Returns
Both companies are betting their futures on AI paying off handsomely. Microsoft's AI business has already hit an annual revenue run rate of $37 billion, a 123% increase from a year ago, and its AI-powered Copilot now has over 20 million paid seats. The company's massive $627 billion backlog of future contracted revenue signals that demand is not the issue; fulfilling it is. CEO Satya Nadella has acknowledged that supply will remain constrained. Amazon, meanwhile, is seeing explosive growth in its own AI services like Bedrock, with CEO Andy Jassy highlighting that its custom Trainium AI chips will save the company billions. Analysts are now debating which company will deliver superior returns on their massive AI investments. While Microsoft has the early lead in AI-fueled growth, some analysts believe Amazon’s diversified business and custom silicon strategy could give it an edge in the long run.
