Amazon’s 39% AWS Operating Margin the Single Best Reason to Buy the Stock in September

During Amazon’s second quarter of 2026, AWS posted a breathtaking 64% year‑over‑year increase in operating profits, delivering an unprecedented 39% operating margin.

This margin stands out starkly alongside the other major business segments. While North American and international commerce combine to generate roughly 80% of total sales, they contribute only about 40% of operating profit. Conversely, AWS captures less than 30% of revenue yet generates almost 60% of operating profit.

The primary driver of this dramatic disparity is AWS’s superior unit economics.

Because AWS yields substantially higher profit per dollar of revenue, it skews the overall average upward. Management has explicitly stated that the company will continue to pour capital into infrastructure expansion, expecting continued growth at a 37% annual rate through 2027. Analysts note that compute capacity is already strained, with demand projected to remain ahead of supply in 2026 and beyond.

With AWS serving as the primary engine, robust growth in this segment acts as a potent catalyst for total shareholder returns. Massive investments in data center capacity are positioned to deliver swift returns, and the trajectory suggests further acceleration as Amazon leverages its dominant cloud position earlier than many anticipate.

Investors may recall landmark moments such as the 2009 inflection point where early exposure to Nvidia produced outsized returns. Today, the structural advantage displayed by AWS mirrors earlier turning tapes in financial markets.

Amazon’s most profitable business segment continues to expand at the fastest pace of any unit, creating a durable competitive moat.
The relentless expansion of AWS infrastructure is poised to amplify free cash flow generation and improve earnings quality well into the mid‑decade.

Given the combination of rapid revenue growth, expanding absolute margins, and constrained execution risks outside of cloud services, the current valuation reflects limited risk premium compared to the underlying performance. For investors seeking alpha driven by fundamental strength, the margin dynamics of AWS represent a compelling entry point.