Turning 65 unlocks a rarely used feature of a health savings account: after that birthday, its funds can pay Medicare premiums with no tax and no penalty. Most insurance premiums never qualify as a tax-free HSA expense, but Medicare is a specific exception carved into federal rules. For retirees who built a balance during their working years, the account can quietly become one of the few ways to cover Part B, Part D and Medicare Advantage costs with pre-tax dollars — a benefit that stops abruptly at the Medigap line.
Which Medicare costs an HSA can cover after 65
IRS Publication 969 lists Medicare and other health coverage for people 65 and older as a qualified HSA expense, with one notable carve-out: premiums for a Medicare supplement policy, or Medigap, do not count. The publication allows tax-free withdrawals for Part B, Part D and Part C (Medicare Advantage) premiums, so an account holder can route those recurring costs through the account and keep the money entirely untaxed.
Because the standard Part B premium is deducted directly from a monthly Social Security payment for most enrollees, as Medicare’s guidance on paying premiums describes, reimbursement is the practical route. The retiree pays the premium through the Social Security deduction and then withdraws an equal amount from the HSA tax-free, keeping records to show the withdrawal matched a qualified cost.
Medicare premiums are not trivial. The standard costs of Part B and Part D, combined with any Advantage or drug-plan charges, can total thousands of dollars a year for a household with two enrollees. Drawing those payments from an HSA lets a retiree spend the account on exactly what it was built to cover, without the income tax that applies to a traditional retirement withdrawal.
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The trade-off: enrolling in Medicare ends HSA contributions
The same rules that let an HSA pay Medicare premiums also shut off new deposits. Once a person enrolls in any part of Medicare, including premium-free Part A, the HSA contribution limit drops to zero. A worker who stays on the job past 65 and delays Medicare can keep contributing, but signing up starts the clock on that ability, permanently.
Timing matters because Part A enrollment can be backdated up to six months for someone who claims Social Security after 65. That look-back can create excess HSA contributions covering months already tied to Medicare, and excess contributions carry a tax penalty unless removed in time. Stopping HSA deposits well before the Medicare start date avoids that trap.
The rules also reward finishing the year strong. Under the last-month rule, someone who is HSA-eligible on the first day of the final month of the year can generally contribute the full annual maximum, but must stay eligible through a testing period the following year or face taxes on the excess — another reason to map the Medicare start date carefully before making a final deposit.
The catch-up contribution that can boost a late balance
Workers who start saving in an HSA later in their careers get a built-in accelerator. Once an account holder turns 55, federal rules allow an extra catch-up contribution of $1,000 a year on top of the standard limit, a figure set directly by statute rather than adjusted for inflation, which is why it has stayed at $1,000 for years. For a couple, each spouse who is 55 or older can make the full catch-up, but only into an HSA in that spouse’s own name — a catch-up cannot be doubled up in a single account.
Those years between 55 and Medicare enrollment are often the last and best window to build the balance. A worker who delays Medicare while covered by a qualifying high-deductible plan at work can keep contributing the standard amount plus the catch-up right up to the month before Medicare begins. Front-loading the account during that stretch is what later makes it possible to cover years of Part B, Part D and Advantage premiums tax-free, turning a modest late start into a meaningful cushion.
How the account changes character at 65
An HSA behaves differently after 65 in a second way. Before that age, a withdrawal for anything other than a qualified medical expense triggers ordinary income tax plus a 20% penalty. After 65, the penalty disappears, and a non-medical withdrawal is taxed like a traditional IRA distribution, which makes the account flexible even for a retiree whose medical spending stays low.
That flexibility is why some savers treat an HSA as a supplemental retirement account, paying current medical bills out of pocket and letting the balance grow untouched. When Medicare arrives, the accumulated funds can absorb years of premiums tax-free, and anything left can go toward other qualified costs such as dental, vision, hearing and certain long-term-care premiums within IRS limits.
The result is a narrow but valuable rule: the HSA a worker funds before 65 becomes, after that birthday, a tax-free source for most Medicare premiums, with Medigap the clear exception and the loss of new contributions the clear cost. Confirming which premiums qualify against Publication 969 before withdrawing keeps the tax treatment intact and the account working as intended.
This article was researched and drafted with the assistance of AI and reviewed by The Money Overview editorial team.
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