A health savings account, or HSA, is a tax-advantaged account for medical expenses, available only to people covered by a qualifying high-deductible health plan (HDHP). What makes it unusual is a rare triple tax advantage: the money you put in is deductible, it grows tax-free, and withdrawals for qualified medical costs are never taxed. In 2026 you can contribute up to $4,400 with self-only coverage or $8,750 with family coverage, according to the IRS. Used well, an HSA is both a way to pay for care and one of the most tax-efficient accounts in the US code.

What an HSA is

An HSA is an account you own, held at a bank or HSA provider, that pairs with a high-deductible health plan. Because the plan leaves you exposed to more upfront medical costs, the account is meant to help you cover them with pre-tax dollars. The money is yours permanently: unlike a flexible spending account, an HSA is not use-it-or-lose-it, the balance rolls over every year, and it stays with you when you change jobs or health plans. Many providers also let you invest the balance once it passes a threshold, so it can grow like a retirement account.

The triple tax advantage

This is the heart of it, and almost no other account offers all three. Per IRS Publication 969: contributions are deductible even if you do not itemize, and contributions made through an employer's payroll are excluded from your income entirely; the earnings on the account are not taxed while they stay in it; and distributions used for qualified medical expenses are not taxed. A traditional 401(k) taxes you on the way out; a Roth taxes you on the way in; an HSA, used for medical costs, is taxed on neither side. For how those other accounts compare, see our guide to a Roth IRA versus a 401(k).

2026 and 2027 contribution limits

For 2026, the IRS sets the HSA contribution limit at $4,400 for self-only HDHP coverage and $8,750 for family coverage (Revenue Procedure 2025-19). If you are 55 or older, you can add a $1,000 catch-up contribution on top, an amount fixed by statute that does not rise with inflation. The limits are indexed and step up most years: for 2027 they increase to $4,500 self-only and $9,000 family (Revenue Procedure 2026-24). The limit that applies is the one for the year the contribution is for, and you generally have until the tax-filing deadline the following spring to make a prior-year contribution.

The high-deductible plan requirement

You can only open or contribute to an HSA if you are covered by a qualifying HDHP and have no other disqualifying coverage. For 2026, the IRS defines an HDHP as a plan with a minimum annual deductible of $1,700 for self-only coverage or $3,400 for family coverage, and an out-of-pocket maximum no higher than $8,500 self-only or $17,000 family. Enrolling in Medicare ends your eligibility to contribute, though you can still spend what is already in the account. Check your plan's paperwork for the words HSA-eligible, because not every high-deductible plan qualifies.

What counts as a qualified expense

Qualified medical expenses are broad: doctor visits, prescriptions, dental and vision care, many over-the-counter items, and more, as set out in IRS guidance. Spend the money on those and the withdrawal is tax-free at any age. Spend it on something else and the rules bite: before age 65, a non-qualified withdrawal is taxed as income plus a 20% penalty. From age 65, the 20% penalty disappears, and a non-qualified withdrawal is simply taxed as ordinary income, which makes an HSA behave like a traditional retirement account for non-medical spending in later life.

HSA versus FSA

People often confuse an HSA with a flexible spending account (FSA). The key differences: an HSA requires an HDHP, the money rolls over and is yours to keep, and you can invest it; an FSA is offered through an employer, generally must be spent within the plan year (with limited carryover), and is not portable. The HSA's permanence and its investment option are what let it double as a long-term savings vehicle.

Using an HSA as a long-term account

Because the balance rolls over and can be invested, some people treat an HSA as a stealth retirement account: they pay current medical bills out of pocket, leave the HSA invested to grow for years, and keep receipts to reimburse themselves tax-free later. That approach suits people who can comfortably cover out-of-pocket costs from cash and who want another tax-advantaged bucket after funding other accounts. It is not for everyone; if money is tight, the account is there to pay for care now, which is its primary job. Whether an HSA fits depends on your health plan, your cash flow and your tax situation, so the figures here are a starting point, not a personalized recommendation. You can see how gains are taxed in ordinary accounts by comparison in our guide to capital gains tax.

What to watch

Confirm your plan is HSA-eligible before you count on contributing, note the catch-up if you are 55 or older, and remember the limits reset each year. The numbers that matter are the contribution limit for your coverage, the deductible and out-of-pocket figures that define an eligible plan, and the age-65 line that changes how non-medical withdrawals are taxed. As with any tax account, how much it helps depends on your own bracket and spending.