You can’t contribute to your HSA once your Medicare coverage begins. However, you can use money that is already in your HSA.
You can use money in your HSA to help pay for Medicare premiums (if you’re billed directly), deductibles, coinsurance, and copayments.
TIP: Instead of funding an HSA, you can choose a Medicare Medical Savings Account (MSA) plan under Medicare. This is a type of high-deductible Medicare plan with a medical savings account (although note you cannot fund your own MSA, instead it is funded by Medicare).
TIP: If you or your employer do contribute after you enroll in Medicare you may have to pay a tax penalty. To avoid a tax penalty, you should stop contributing to your HSA at least 6 months before you apply for Medicare.
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