Some enrollees could be hit with increases of more than 20% because of federal changes and higher health expenses.

Centene generates most of its revenue from Medicaid; Obamacare, which Centene refers to as Marketplace; and Medicare health coverage for seniors.

U.S. insurers are requesting the biggest premium increases for Obamacare plans since 2018, according to an analysis by health-research firm KFF, prompted by the looming expiration of premium tax credits and potential tariffs on medical goods.