If you have an HSA and you will soon be eligible for Medicare, it is important to plan ahead and understand how enrolling in Medicare will affect your HSA.
You cannot continue to contribute to an HSA once you have Medicare.
If you retire post 65 (post Medicare age), when you enroll in Medicare at retirement, your Medicare effective date will be retroactive by six months. *** You should stop all HSA contributions up to six months prior to retirement if you are Medicare age + six months (age 65 ½)
If you do not stop contributing the six months before you apply for Social Security, you may have a tax penalty. The penalty is because you were not supposed to put money into your HSA while you had Medicare.