AdventHealth (formerly Adventist Health System) is a faith-based, non-profit health care system headquartered in Altamonte Springs, Florida, that operates facilities within nine states across the United States. The Adventist Health System was rebranded AdventHealth on January 2, 2019. It is the largest not-for-profit Protestant health care provider and one of the largest non-profit health systems in the nation. It has 45 hospital campuses, more than 8,200 licensed beds in nine states, and serves more than five million patients annually.

At the behest of Ellen G. White, the Seventh-day Adventist Church first established the Western Health Reform Institute in Battle Creek, Michigan, in 1866. Over the years, other Adventist sanitariums were established around the country. These sanitariums evolved into hospitals, forming the core of Adventists' medical network.