Fortune 500 vs S&P 500

When you read financial news, you will frequently hear analysts mention the Fortune 500 and the S&P 500. Because both include the number 500 and feature many of the same major U.S. corporations, it is easy to assume they are interchangeable.

However, these two lists serve entirely different purposes, are measured by completely different metrics, and are compiled by different organizations. One is a magazine's ranking of massive sales numbers, while the other is the foundational benchmark for the U.S. stock market.

The Fortune 500: Ranked by Revenue

The Fortune 500 is an annual list published by Fortune magazine that ranks the 500 largest United States corporations strictly by total revenue for their respective fiscal years. It is essentially a measure of sheer size in terms of sales dollars coming through the door.

Because the only requirement is massive revenue, businesses operating in low-margin industries with high volumes of goods—such as retail and grocery chains—often dominate the top spots. They move a lot of product, generating enormous top-line revenue, even if their actual profit margins are thin.

The S&P 500: The Market Cap Index

The Standard & Poor's 500, commonly known as the S&P 500, is a stock market index tracking the stock performance of 500 of the largest companies listed on stock exchanges in the United States. Unlike a simple revenue ranking, this is an actively maintained financial instrument used by investors to gauge the overall health of the stock market.

To be included in the S&P 500, a company must meet strict liquidity requirements, have a minimum market capitalization, and report positive earnings over the most recent four quarters. If you are interested in learning more about how these funds work, check out our guide on what stocks are or explore S&P 500 index funds.

The Walmart Example: Why The Lists Differ

The easiest way to understand the difference is to look at the top company on each list.

However, Walmart is rarely in the top 10 of the S&P 500. The S&P 500 is weighted by market capitalization (what investors believe the company is currently worth). Tech giants like Apple, Microsoft, and Nvidia have significantly higher profit margins and growth expectations. Therefore, the stock market values those tech companies much higher than Walmart, placing them at the top of the S&P 500, even though their raw sales figures might be lower.

Can a Company Be on Both Lists?

Absolutely. Many of the largest companies in the world—like Apple, Amazon, and Alphabet—are so massive that they generate enough revenue to rank highly on the Fortune 500, while also maintaining the high market capitalization required to dominate the S&P 500.

Conversely, a massive privately owned company like Publix Super Markets generates enough grocery sales to easily make the Fortune 500. But because you cannot buy shares of Publix on the public stock exchange, it will never appear in the S&P 500.