A health savings account is unique: contributions are deductible, growth is tax-free, and withdrawals for qualified medical costs are tax-free too. No other account gives all three.
After age 65 you can withdraw for any purpose paying only ordinary income tax — effectively a second traditional IRA, with the medical use staying tax-free.
Because the triple advantage compounds, many people who can afford to pay medical costs out of pocket invest the HSA instead and let it grow untouched.
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