You must be enrolled in a qualified High-Deductible Health Plan (HDHP). You cannot be claimed as a Tax Dependent.
You cannot be enrolled in Medicare, Tricare, another group medical plan (your spouse’s plan, for example), a Health Flexible Spending Account, or a Health Reimbursement Arrangement.
Domestic Partners of the account holder must set up a separate account and may contribute up to the family limit; the account holder cannot use their account to pay a Domestic Partner’s expenses.
If unsure about your eligibility, please consult your tax advisor or IRS publication 969.