A health savings account (HSA) is a tax-advantaged medical savings account available to taxpayers in the United States who are enrolled in a high-deductible health plan (HDHP). The funds contributed to an account are not subject to federal income tax at the time of deposit. Unlike a flexible spending account (FSA), HSA funds roll over and accumulate year to year if they are not spent. HSAs are owned by the individual, which differentiates them from company-owned Health Reimbursement Arrangements (HRA) that are an alternate tax-deductible source of funds paired with either high-deductible health plans or standard health plans.