The United States is home to many of the world’s most valuable publicly traded companies by market capitalisation. But which firms currently hold the top positions by market value?
We’ve reviewed the largest US companies by market capitalisation – calculated by multiplying a company’s share price by the total number of outstanding shares – as of 5 May 2026.
The largest US companies by market cap
Our rankings below show the leading US-listed companies by market capitalisation as of 5 May 2026. Each company’s market cap is given in USD, together with its most recent share price.
| Rank | Company | Market cap (USD) | Share price (USD) |
|---|---|---|---|
| 1 | NVIDIA | $4.8tn | $198.48 |
| 2 | Alphabet (Google) | $4.6tn | $379.64 |
| 3 | Apple | $4.1tn | $276.83 |
| 4 | Microsoft | $3.1tn | $413.62 |
| 5 | Amazon | $2.9tn | $272.05 |
| 6 | Broadcom | $2tn | $416.50 |
| 7 | Meta Platforms (Facebook) | $1.5tn | $610.41 |
| 8 | Tesla | $1.5tn | $392.51 |
| 9 | Walmart | $1tn | $130.33 |
| 10 | Berkshire Hathaway | $1tn | $468.52 |
The information on this page is based on data from public company disclosures, including SEC filings and EDGAR. It is provided for informational purposes only and does not constitute investment advice or a recommendation to trade. While believed to be accurate as of the stated date, figures may change without notice.
How market capitalisation works
Market capitalisation is calculated by multiplying a company's current share price by its total number of outstanding shares (Fidelity, 31 March 2026). It shows the market's valuation of a business at a specific point in time, rather than its book value or revenue. A company with a high share price and fewer shares can therefore have a smaller market cap than one with a lower share price and a much larger share count (Aquis Capital, 18 September 2025). This makes market cap a useful standardised measure for comparing companies across sectors and indices, as well as for assessing portfolio weighting, index inclusion, and investment mandates.
What drives changes in market cap rankings
Market cap rankings change as share prices move, even when the number of outstanding shares stays the same. Earnings releases, macroeconomic data, interest rate expectations, regulation, and sector sentiment can all affect valuations. Rising rates can weigh on high-growth companies by increasing the discount rate applied to future cash flows – an effect that is more pronounced for growth stocks, whose earnings are expected further into the future, making a larger share of their cumulative cash flows subject to multi-year compounding of the discount rate (Investopedia, 20 January 2026). Share buybacks may also influence market cap dynamics: by reducing shares outstanding, a buyback increases earnings per share and, assuming the price-to-earnings multiple holds, can support a higher share price – though the overall market cap effect still depends on price movements and company fundamentals (Investopedia, 24 March 2026).
US equity markets and index composition
The largest US companies by market cap are usually listed on the NYSE or the Nasdaq, and many are included in major indices such as the S&P 500, the Nasdaq-100, and the Dow Jones Industrial Average. Index membership can significantly influence trading volumes because passive funds hold companies in line with their index weightings – passive large-cap categories collected more than $380bn in assets in 2025, largely through ETFs tracking the S&P 500, with passively managed funds now accounting for over 55% of total net assets in the US funds market (Morningstar, 16 January 2026). Research shows that inflows into passive funds disproportionately raise the stock prices of the largest companies in an index, with the biggest S&P 500 constituents historically experiencing the highest returns and greatest increases in volatility following passive fund inflows (Morningstar, 26 June 2025). When a company's market cap rises relative to peers, more passive capital may flow into it; if its weighting falls, the process can work in reverse, amplifying moves in the largest constituents alongside earnings, macro conditions, and investor sentiment.
Explore more of our rankings
- Largest companies by market cap
- Largest tech companies by market cap
- Largest UK companies by market cap
Learn more about market capitalisation.
FAQ
What is US stock investing?
US stock investing means gaining exposure to publicly traded American companies. This can involve buying shares directly or trading derivatives such as contracts for difference (CFDs) that let you speculate on price movements without owning the underlying asset. CFDs are complex instruments that use leverage and carry a high risk of losing money quickly. Prices may be affected by investor sentiment, earnings reports, and broader economic conditions.
How do I trade US stocks?
To trade US share CFDs, you'll need to open and verify an account with a locally authorised and regulated provider. Once registered, you can deposit funds and access a trading platform. It’s important to understand how the market works, research the companies you’re interested in, and consider practising with a demo account before trading with real money. CFDs are traded on margin – leverage amplifies both profits and losses.
What should beginners consider when trading US stocks?
CFDs involve significant risk, and many retail CFD accounts lose money. Start by researching a company’s financial position, market role, and potential outlook. Begin with small position sizes to help manage the risks of leverage. Use straightforward strategies while learning, and make use of risk management tools such as stop-loss orders. Be clear on how margin calls work, and never trade with more than you can afford to lose. Understand that stop-loss orders are not guaranteed, while guaranteed stop-loss orders incur a fee if activated.