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The S&P 500 consists of 500 companies that have issued a total of 504 stocks. Some companies such as Alphabet have issued multiple classes of shares. The top 10 largest holdings are listed on the official S&P Global website. An S&P 500 company must meet specific requirements to be included as a constituent within the index.
S&P doesn’t provide the total list of holdings, however, at least not for free. Subscribers to S&P’s research unit, Capital IQ, can get access to the entire list. S&P 500 companies represent the top companies within their industries and they’re a gauge of U.S. economic activity.
Key Takeaways
- The S&P 500 includes some of the top companies that are leaders within their industries and represent a gauge of the U.S. economy.
- Companies must meet certain requirement criteria determined by the publishers of the index before being added to the S&P.
- The S&P 500 index is market capitalization-weighted so it gives a higher percentage allocation to companies with the largest market cap.
- To join the S&P 500, a stock must meet certain criteria, including a total market cap of $22.7 billion.
- Companies can be removed from the S&P 500 if they deviate substantially from these standards.
S&P 500 Inclusion Criteria
The S&P 500 was created in 1957 and it’s one of the most widely quoted stock market indexes. S&P 500 stocks represent the largest publicly traded companies in the U.S. The S&P 500 focuses on the U.S. market’s large-cap sector.
An S&P 500 company must meet a broad set of criteria to be added to the index:
- It must have a total market capitalization of at least $22.7 billion.
- Must be a U.S. company
- A float-adjusted liquidity ratio (FALR) greater than or equal to 0.75
- A positive sum of the most recent four consecutive quarters of trailing earnings
- Positive earnings for its most recent quarter
- Must meet certain liquidity requirements
Companies may be removed from the S&P 500 if they deviate substantially from these standards.
$52.8 Trillion
The total combined market cap of the 504 constituents in the S&P 500 as of July 1, 2025.
S&P 500 Calculation
The S&P 500 is a free-float market capitalization-weighted index. Market capitalization represents the total dollar market value of a company’s outstanding equity shares. Market cap is calculated by multiplying the total number of outstanding shares of stock by the company’s current stock price. A company with 20 million shares outstanding in which its stock is selling for $100 per share would have a market cap of $2 billion.
The more valuable an individual company’s stock becomes, the more it contributes to the S&P 500’s overall return as a result. It’s not uncommon for three-quarters of the index’s return to be linked to only 50 to 75 stocks.
The addition or subtraction of smaller companies from the index therefore doesn’t have a noticeable impact on the overall return of the index. The removal or addition of even just one of the largest stocks can have a major effect, however.
S&P 500 Sector Breakdown
These are the top sectors and their weightings within the S&P 500 index as of Feb. 25, 2025.
| S&P 500 Sector Weighting | |
|---|---|
| Sector | Index Weighting |
| Information Technology | 31.6% |
| Financials | 14.3% |
| Consumer Discretionary | 10.6% |
| Healthcare | 9.6% |
| Communication Services | 9.6% |
| Industrials | 8.7% |
| Consumer Staples | 5.9% |
| Energy | 3.0% |
| Utilities | 2.5% |
| Real Estate | 2.1% |
| Materials | 1.9% |
Being aware of the S&P’s sector weighting is important because sectors with a smaller weighting may not have a material impact on the value of the overall index. This can be the case even if they’re outperforming or underperforming the market.
If oil prices are rising and leading to increased profits for the energy sector, those stocks represent only 3.0% of the S&P 500. Oil stocks may not lead to a higher S&P if the more heavily weighted information technology sector is underperforming.
Important
S&P 500 components are weighted by free-float market capitalization so larger companies can affect the value of the index to a greater degree.
Top 25 Components by Market Cap
The exact weightings of the top 25 components aren’t available from S&P directly so the weightings below are from the SPDR S&P 500 Trust ETF (SPY). SPY is the oldest exchange-traded fund (ETF) that tracks the S&P 500. It holds $659 billion in assets under management (AUM) as of Sep. 9, 2025 and is highly traded.
The SPY’s portfolio weightings provide a good proxy for investing in the underlying S&P 500 index as a result. The two may not be exactly the same, however. These are the 25 largest S&P 500 index constituents by weight as of Sep. 9, 2025:
Nvidia (NVDA) 8.06%
Microsoft (MSFT) 7.37%
Apple (AAPL) 5.76%
Amazon.com (AMZN) 4.11%
Meta Platforms (META) 3.12%
Broadcom (AVGO) 2.57%
Alphabet Class A (GOOGL) 2.08%
Alphabet Class C (GOOG) 1.68%
Berkshire Hathaway (BRK.B) 1.61%
Tesla (TSLA) 1.61%
JPMorgan Chase (JPM) 1.53%
Visa (V) 1.10%
Eli Lilly (LLY) 1.08%
Netflix (NFLX) 0.92%
Exxon Mobil (XOM) 0.89%
Mastercard (MA) 0.85%
Walmart (WMT) 0.79%
Costco (COST) 0.77%
Oracle (ORCL) 0.77%
Johnson & Johnson (JNJ) 0.74%
Home Depot (HD) 0.68%
Procter & Gamble (PG) 0.66%
Palantir Technologies (PLTR) 0.63%
AbbVie (ABBV) 0.62%
Bank of America (BAC) 0.58%
How Many Companies Are in the S&P 500?
There were generally 500 companies within the index but that number has grown to 503 stocks as of Sep 1, 2025 because some companies such as Alphabet have multiple classes of equity shares.
How Are Companies Selected for the S&P 500?
A company must meet certain requirements for inclusion in the S&P 500, which include:
- A market cap of at least $22.7 billion
- Must be a U.S. company
- A float-adjusted liquidity ratio (FALR) greater than or equal to 0.75
- Positive earnings over the most recent four consecutive quarters summed together
- A profitable earnings report for the company’s most recent quarter
- Liquidity requirements
How Can I Buy the S&P 500?
The S&P 500 is an index so it can’t be purchased directly but exchange-traded funds that mirror or track the index can be purchased. They include the State Street Global Advisors’ SPDR S&P 500 Trust ETF (SPY).
The Bottom Line
The top 25 companies in the S&P 500 are some of the most well-known companies in the world. A large portion of the top 10 are tech companies such as Apple, Microsoft, and Google. Investors can purchase the individual stocks of the companies or invest in a fund that tracks the S&P 500.
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