Reclaim your health with us! This article helps you understand Health Savings Accounts and Flexible Savings Accounts, and covers: What is a Health Savings Account (HSA)? What is a Flexible Savings Account (FSA)? What is the difference between an HSA and an FSA? What expenses should you use an HSA or FSA for? What happens to the HSA or FSA money you don’t use? What happens to your HSA or FSA if you leave your job?