Here's how these seven Fortune 500 health insurance companies ranked according to membership in the first quarter of 2021:
1. UnitedHealth Group: 49.5 million members
2. Anthem: 43.5 million members
3. Centene: 25.1 million members
4. CVS Health (Aetna): 23.6 million members
5. Humana: 16.95 million members
6. Cigna: 16.7 million members
7. Molina Healthcare: 4.6 million members