HSAs are tax-advantaged savings accounts for health care services. A person must enroll in a qualified High-Deductible Health Plan (HDHP) before they can establish a HAS (Health Savings Account). It is a healthcare plan that allows an individual to contribute pre-tax money to be used for qualified medical expenses. HSAs, which are portable, must be linked to a high-deductible health insurance policy. It is the newest account made possible with the Medicare Modernization Act. It refers to a trust created exclusively for the purpose of paying the qualified medical expenses of the account beneficiary, but only if certain specifications or eligibility criteria are met.