Medicare Overview 

Medicare is health insurance provided to more than 66 million people in the United States by the federal government. Administered by the Centers for Medicare & Medicaid Services (CMS), Medicare is available to people 65 and older, under 65 with certain disabilities, or any age with end-stage renal disease (ESRD) or ALS.  

Medicare Eligibility 

Generally, you are eligible for Medicare if you are age 65 or older, or if you receive Medicare disability benefits, regardless of your age. 

• If you retire when you are age 65 or older, you are immediately eligible for Medicare assuming you or your spouse have paid Medicare taxes for at least ten years.
• If you retire before age 65, you become eligible for Medicare at age 65.
• Once you are eligible for Medicare, it becomes your primary medical coverage. Any additional coverage you have will “supplement” what Medicare doesn’t cover.
• Medicare eligibility is determined on an individual basis. For example, your spouse may be Medicare-eligible while you remain non-eligible—or vice versa.
• Unless you have a Medicare disability, you are non-Medicare eligible while you are under age 65, even if you retire earlier than that age. 

When to Enroll 

Your Initial enrollment period is a seven-month window that starts three months before you turn 65 and ends three months after. There are also special enrollment periods if you miss this window, like if you’re still working and covered under a group health plan. 

What Does Medicare Cover? 

• Medicare Part A: Helps pay for inpatient care in a hospital or skilled nursing facility (following a hospital stay), and some home health care and hospice care.
• Medicare Part B: Helps pay for doctors’ services and other medical services and supplies not covered by Medicare Part A. Premiums apply.
• Medicare Part C (also known as Medicare Advantage): Provides Medicare-approved plans available through private insurers. These plans must offer the benefits of Medicare Part A and B, but many plans offer more, including coverage from Part D.
• Medicare Part D: Helps pay for prescription drugs doctors prescribe for treatment. Part D is not considered part of “basic” Medicare coverage and is run by private companies with plans approved by the federal government. Premiums apply. 

Once you become Medicare-eligible, Medicare becomes your primary insurer and covers approximately 80 percent of the cost of your Part A and Part B expenses. However, basic Medicare does not cover all your medical expenses, so many people choose to purchase supplemental coverage. 

HSA and Medicare 

Options After Age 65 

If you enroll in Medicare at the age of 65 or older, you may still use your HSA for health care expenses. However, you are not allowed to make further contributions, as you are no longer enrolled in a qualified High Deductible Health Plan. 

If you delay your enrollment in Medicare, you can continue to make contributions past the age of 65, as long as you are still covered by an HSA qualified High Deductible Health Plan. You can also make $1,000 yearly catch-up contributions. 

Medicare Premiums 

Once you are 65 and eligible for Medicare, you can use your HSA to pay Medicare premiums (A, B, C, and D), out-of-pocket expenses that Medicare does not pay, and Medicare HMO premiums. You cannot pay Medigap premiums with your HSA. Medigap is insurance that individuals can buy to cover out-of-pocket costs not covered by Medicare.