Any unused HSA funds remain in your account from year to year and earn interest or investment returns. And if you leave Morgan Stanley or select a Medical Plan option other than Option C, your HSA funds are yours to keep. The account is portable, even if you become unemployed, self-employed or employed at a small business and no longer receive insurance through an employer.

Once your balance reaches $500, you can also invest HSA funds over that amount, choosing from a range of investment options.