The healthcare sector includes companies that produce medical goods, such as drugs and medical devices, and companies that provide medical services, such as health insurance or hospital administration. Here are the 10 biggest healthcare companies based on 12-month trailing (TTM) revenue as of March 24, 2020. This list is limited to companies which are publicly traded in the U.S. or Canada, either directly or through ADRs.

#1 CVS Health Corp. (CVS)

  • Revenue (TTM): $257.3 billion
  • Net Income (TTM): $6.6 billion
  • Market Cap: $69.2 billion
  • 1-Year Trailing Total Return: -2.1%
  • Exchange: New York Stock Exchange

The parent company of a leading drugstore chain, CVS Health Corp. also is among the biggest pharmacy benefit management (PBM) companies. Additionally, through its 2018 acquisition of Aetna, CVS has become a major player in health insurance.

#2 UnitedHealth Group Inc. (UNH)

  • Revenue (TTM): $240.3 billion
  • Net Income (TTM): $13.8 billion
  • Market Cap: $184.8 billion
  • 1-Year Trailing Total Return: -19.8%
  • Exchange: New York Stock Exchange

UnitedHealth Group is a health insurance company that also provides data analytics and consulting services to healthcare providers, as well as pharmacy care services. Its principal divisions include UnitedHealthcare, OptumHealth, OptumInsight, and OptumRx.

#3 McKesson Corp. (MCK)

  • Revenue (TTM): $224.9 billion
  • Net Income (TTM): -$917.0 million
  • Market Cap: $18.7 billion
  • 1-Year Trailing Total Return: -1.2%
  • Exchange: New York Stock Exchange

McKesson Corp. is a distributor of pharmaceuticals and other medical products in the U.S., Canada, and Europe. Bansi Nagji, executive vice president and chief strategy and business development officer, is stepping down from this role effective March 31, 2020. He will remain with the company in an advisory role to smooth the transition. McKesson expects to name a successor within the next few months.

#4 AmerisourceBergen Corp. (ABC)

  • Revenue (TTM): $182.1 billion
  • Net Income (TTM): $649.4 million
  • Market Cap: $15.2 billion
  • 1-Year Trailing Total Return: -4.4%
  • Exchange: New York Stock Exchange

AmerisourceBergen Corp. is a distributor of medications and medical supplies. The company is in the process of exiting its PharMEDium compounding business as the result of "ongoing operational, regulatory, and commercial challenges."

#5 Cigna Corp. (CI)

  • Revenue (TTM): $153.7 billion
  • Net Income (TTM): $5.1 billion
  • Market Cap: $48.4 billion
  • 1-Year Trailing Total Return: -21.7%
  • Exchange: New York Stock Exchange

Cigna Corp. offers medical, life, and accident insurance products, as well as managed care services.

#6 Cardinal Health Inc. (CAH)

  • Revenue (TTM): $149.7 billion
  • Net Income (TTM): -$4.2 billion
  • Market Cap: $12.0 billion
  • 1-Year Trailing Total Return: -12.3%
  • Exchange: New York Stock Exchange

Cardinal Health is a manufacturer of medical, surgical, and laboratory products, as well as a distributor of drugs and healthcare supplies. Effective May 12, 2020, Jason Hollar will assume the CFO post at Cardinal Health. He was most recently the chief financial officer (CFO) of automotive products and services company Tenneco Inc. (TEN).

#7 Walgreens Boots Alliance Inc. (WBA)

  • Revenue (TTM): $137.4 billion
  • Net Income (TTM): $3.7 billion
  • Market Cap: $38.6 billion
  • 1-Year Trailing Total Return: -27.8%
  • Exchange: Nasdaq

Walgreens Boots Alliance operates drug stores in the U.S. under the Walgreens and Duane Reade names, as well as Boots drug stores in the U.K. and various other countries. In the U.S. during recent years, Walgreens has acquired a large number of store locations from competitor Rite Aid Corp. (RAD). The company is also a distributor of drugs and medical products, as well as the parent of online stores such as Drugstore.com, VisionDirect.com, and Beauty.com.

#8 Anthem Inc. (ANTM)

  • Revenue (TTM): $104.2 billion
  • Net Income (TTM): $4.8 billion
  • Market Cap: $44.1 billion
  • 1-Year Trailing Total Return: -41.4%
  • Exchange: New York Stock Exchange

Anthem is a health insurance company that offers individual, employer-sponsored, Medicare, and Medicaid plans. In 2020, Anthem completed the acquisition of Beacon Health Options, "the largest independently held behavioral health organization in the country serving more than 36 million people across all 50 states."

#9 Johnson & Johnson (JNJ)

  • Revenue (TTM): $82.1 billion
  • Net Income (TTM): $15.1 billion
  • Market Cap: $293.0 billion
  • 1-Year Trailing Total Return: -16.6%
  • Exchange: New York Stock Exchange

Johnson & Johnson manufactures prescription pharmaceuticals, over-the-counter healthcare products, and medical devices. BAND-AID brand adhesive bandages are among its best-known consumer products. While noting that they are working with multiple organizations to develop "fast-track solutions" for the COVID-19 coronavirus, Johnson & Johnson warns investors to discount "anecdotal, unsubstantiated reports" that HIV treatment darunavir (DRV) may be effective against COVID-19. The company is screening various antiviral compounds, including darunavir, as possible COVID-19 treatments, but it is too early to tell which, if any, may prove to be effective.

#10 Centene Corp. (CNC)

  • Revenue (TTM): $74.6 billion
  • Net Income (TTM): $1.3 billion
  • Market Cap: $26.7 billion
  • 1-Year Trailing Total Return: -20.3%
  • Exchange: New York Stock Exchange

Centene Corp. is a managed healthcare company, focusing on administering government-sponsored programs. In January 2020, Centene acquired WellCare Health Plans Inc., thereby increasing its market share in Medicaid, Medicare Advantage, and Medicare Prescription Drug Plans.