Eli Lilly (LLY +1.38%) is the most valuable healthcare company, with Johnson & Johnson (JNJ +0.59%) and AbbVie (ABBV -0.77%) rounding out the top three. Pharmaceutical companies dominate this market sector, comprising over half of the largest healthcare companies by market cap.

Largest companies by market cap in the healthcare sector
(Editor's note: Rankings are as of Oct. 2, 2025.)
1. Eli Lilly

NYSE: LLY
Key Data Points

NYSE: JNJ
Key Data Points

NYSE: ABBV
Key Data Points
- Market cap: $431.71 billion (as of Oct. 2)
- Revenue (TTM): $58.3 billion
- Gross profit (TTM): $41.4 billion
- Five-year annualized return: 28.26%
- Year founded: 2012
AbbVie is a biotechnology company that develops treatments for serious diseases. It has produced therapies for illnesses, including autoimmune diseases, plaque psoriasis, blood cancers, and advanced Parkinson's disease. It also acquired Capstan Therapeutics, a cell and gene therapy company, for $2.1 billion in mid-2025.
AbbVie is a relatively new company that started as a spinoff of Abbott Laboratories. It's now one of the better dividend stocks in the healthcare sector. It has regularly raised its dividend payout, resulting in a high dividend yield.
4. UnitedHealth Group

NYSE: UNH
Key Data Points
- Market cap: $315.45 billion (as of Oct. 2)
- Revenue (TTM): $422.8 billion
- Gross profit (TTM): $88.1 billion
- Five-year annualized return: 3.84%
- Year founded: 1977
UnitedHealth Group provides health insurance and healthcare services. It sells health insurance products through its UnitedHealthcare division and offers healthcare services through its Optum division.
Although UnitedHealth Group is one of the largest healthcare companies, it has faced a number of high-profile issues. A subsidiary, Change Healthcare, was responsible for the largest reported healthcare data breach in history in 2024. CEO Andrew Witty abruptly resigned in May 2025 for personal reasons, and the company replaced its CFO in July. Also in July, UnitedHealth disclosed that it's facing a criminal and civil investigation by the Department of Justice.
5. AstraZeneca

NASDAQ: AZN
Key Data Points
- Market cap: $261.56 billion (as of Oct. 2)
- Revenue (TTM): $56.5 billion
- Gross profit (TTM): $46.0 billion
- Five-year annualized return: 11.76%
- Year founded: 1913 (Astra AB), Zeneca (1993), 1999 (merger of Astra AB and Zeneca)
AstraZeneca is a multinational biotech company formed through the 1999 merger of Astra, a Swiss company, and Zeneca, a British company. Its headquarters are in Cambridge, England.
This company manufactures prescription medications for many major diseases, including cardiovascular disease, metabolic disorders, renal disease, and rare diseases. It has 11 research and development (R&D) centers, 28 manufacturing sites, and a market presence in more than 130 countries.
6. Novartis

NYSE: NVS
Key Data Points
- Market cap: $249.95 billion (as of Oct. 2)
- Revenue (TTM): $55.2 billion
- Gross profit (TTM): $42.1 billion
- Five-year annualized return: 14.07%
- Year founded: 1886 (Sandoz), 1970 (Ciba-Geigy), 1996 (merger of Ciba-Geigy and Sandoz)
Novartis is a Swiss pharmaceutical company. It manufactures prescription drugs for various diseases. Some of its bestselling products include Entresto, a medication used to treat heart failure; Cosentyx, a treatment for psoriasis; and Kesimpta, a treatment for certain forms of multiple sclerosis (MS).
This Swiss company is also incorporating artificial intelligence (AI) technology into its business. Novartis has partnered with Viz.ai to provide AI-powered care for cancer patients.
7. Abbott Laboratories

NYSE: ABT
Key Data Points
- Market cap: $232.30 billion (as of Oct. 2)
- Revenue (TTM): $43.1 billion
- Gross profit (TTM): $24.1 billion
- Five-year annualized return: 6.50%
- Year founded: 1888
Abbott Laboratories manufactures healthcare products and medical equipment. It has four main business segments: established pharmaceutical products, diagnostic products, nutritional products, and medical devices.
Like its spinoff AbbVie, Abbott Laboratories is popular among dividend investors. It has raised its dividend for more than 50 consecutive years, putting it on the list of Dividend Kings.
8. Merck

NYSE: MRK
Key Data Points
- Market cap: $225.12 billion (as of Oct. 2)
- Revenue (TTM): $63.6 billion
- Gross profit (TTM): $48.7 billion
- Five-year annualized return: 6.35%
- Year founded: 1891
Merck is a pharmaceutical company known for its impressive oncology portfolio. That includes its leading drug, Keytruda, which is also the bestselling drug worldwide. Merck also makes diabetes medications, an HPV vaccine, and a chickenpox vaccine.
This company has made several major acquisitions recently. In 2024 alone, it acquired Harpoon Therapeutics, Abceutics, EyeBio, and Modifi Biosciences. In 2025, it acquired SpringWorks Therapeutics for $3.4 billion. Merck is also going through a leadership transition; CEO Belen Garijo will step down at the end of April 2026. Her successor will be Kai Beckmann, head of the company's Electronics business.
9. Thermo Fisher Scientific

NYSE: NVO
Key Data Points
- Market cap: $199.17 billion (as of Oct. 2)
- Revenue (TTM): $49.0 billion*
- Gross profit (TTM): $41.1 billion*
- Five-year annualized return: 13.42%
- Year founded: 1923
*Converted from Danish krone.
Based in Denmark, Novo Nordisk is a leading pharmaceutical company that develops medications for diabetes, weight loss, and rare diseases. It's the maker of Ozempic, a treatment for diabetes, and Wegovy, a weight loss drug.
Novo Nordisk has a market presence in 170 countries. It's one of the biggest companies in Europe, and at one point, its market cap surpassed Denmark's gross domestic product (GDP).
Related investing topics
Healthcare sector takeaways for investors
Investing in healthcare stocks can be challenging. Among the 10 largest healthcare companies, only two have outperformed the S&P 500 over the last five years.
The sector also has some unique risks. The development of new products often requires a lengthy regulatory process, particularly for pharmaceutical companies. And if a company's product may have caused harm to a consumer, there's the possibility of a lawsuit.
Like most businesses, healthcare companies have been affected by the Trump administration's import tariffs. Tariffs could increase the cost of medical devices and lead to pharmaceutical shortages, if they stand. Although a federal court has ruled that the tariffs are illegal, the Trump administration has appealed the ruling. Regardless, Eli Lilly, Johnson & Johnson, and AstraZeneca are all investing heavily to expand their U.S. manufacturing to help reduce the potential impact of tariffs.
Even with those risks, there are also plenty of reasons why healthcare is an attractive sector for investors. Some of the top healthcare companies pay high dividends, which is great for those looking to build passive income. Healthcare stocks also tend to be resistant to market downturns. After all, no matter how the economy is doing, people always need healthcare.