Established by an eligible individual or by an employer for an eligible employee, an HSA is used for paying qualified medical expenses. HSAs combine a savings account with a high-deductible health insurance plan, offering lower health insurance premiums with various tax advantages. Made possible through the Medicare Prescription Drug and Modernization Act, these Archer MSA-like accounts became available on January 1, 2004 for virtually anyone who has coverage under a high-deductible health plan (HDHP).