UnitedHealthcare, Anthem, Aetna, Cigna and Humana are the five largest health insurers in America. To learn more about them, check out a recent paper by Schoen and Collins (2017) in Health Affairs.
The five largest US commercial health insurance companies together enroll 125 million members, or 43 percent of the country’s insured population…In 2016 Medicare and Medicaid accounted for nearly 60 percent of the companies’ health care revenues and 20 percent of their comprehensive plan membership. Although headlines have focused on losses in the state Marketplaces created by the Affordable Care Act (ACA), the Marketplaces represent only a small fraction of insurers’ members.
With CVS and Aetna merging, it will be interesting to see if Aetna’s market share grows or shrinks based on this merger.