Health Savings Accounts

A health savings account (HSA) can make a be a great retirement savings vehicle.
A health savings account is a tax-advantaged medical savings account available to taxpayers in the U.S. who are enrolled in a high-deductible health plan.
As with a traditional 401(k) or IRA, an HSA allows you to set aside pretax money without paying federal or state income tax on it. 
Money in HSAs grow tax-free, and if used for medical expenses, can also be withdrawn tax-free, compared to a traditional 401(k) or IRA, where you pay income tax on your withdrawals.
The biggest payoff with an HSA comes when the money set aside isn’t all used for current medical bills and instead compounds over time before being used for qualified expenses. Once you are enrolled in Medicare you can no longer contribute to an HSA. But you can continue to tap your HSA balance for medical expenses for yourself, your spouse and any dependents you may have.