HSA triple tax advantage
Contributions, growth, and qualified withdrawals are all tax-free. The catch: you must be enrolled in a qualifying high-deductible health plan, and there are annual contribution limits.
discussion, evidence first
Contribution limits and HDHP definitions are set annually by the IRS.
Read the sourceIRS Publication 969, Health Savings Accounts and Other Tax-Favored Health Plans.
Only if you can actually afford to fund it. For someone with high out-of-pocket medical costs, a lower-deductible plan can beat the HSA on total cost.