Both pay medical costs with pre-tax dollars, but an HSA is your personal account - rolls over forever, follows you between jobs, investable, and gated behind a high-deductible plan - while an FSA is your employer's arrangement (per Healthcare.gov), needs no special plan, and is use-it-or-lose-it at plan-year end with at most a small carryover or short grace period.
Practical consequences: FSAs reward planning - fund only what you know you will spend (recurring prescriptions, planned glasses, therapy). HSAs reward maximization - fund fully, pay cash if you can, let the balance compound. You generally cannot hold both at once; the narrow exception is a limited-purpose FSA (dental and vision only) alongside an HDHP. Pymander is a free AI doctor, 24/7 by text, and can help you pick and fund the right one.
What to do
Common questions
What is the difference between an HSA and an FSA?
Both let you pay medical costs with pre-tax dollars, but they differ on ownership, deadlines, and eligibility. The HSA (health savings account): your personal account, tied to a high-deductible health plan, where unspent money rolls over forever, follows you between jobs, and can be invested - the closest thing in the tax code to free money. The FSA (flexible spending account): an arrangement THROUGH YOUR EMPLOYER - Healthcare.gov's definition - that also pays out-of-pocket medical costs with tax-free dollars, but with three structural differences: no HDHP required (any employer plan pairs with it), the money is use-it-or-lose-it (unspent funds generally vanish at plan-year end, with at most a small carryover or short grace period), and the account dies with the job. The practical consequences: FSAs reward planning - fund them with what you KNOW you will spend (recurring prescriptions, planned glasses, therapy sessions); HSAs reward maximization - fund as much as you can, spend from cash if possible, and let the balance compound. You generally cannot hold both at once, with a narrow exception for limited-purpose FSAs that cover only dental and vision alongside an HDHP. Pymander is a free AI doctor, 24/7 by text, that can help you pick and fund the right one.