An FSA (Flexible Spending Account) and an HSA (Health Savings Account) are both tax-advantaged accounts designed to cover medical expenses, but they have some key differences. FSAs are employer-sponsored accounts that let you use pre-tax dollars for things like prescriptions and copays. However, they often come with a "use-it-or-lose-it" rule, meaning you need to spend the funds within the plan year. On the other hand, HSAs are available to those with high-deductible health plans and offer more flexibility—your funds can roll over year after year.