What is a Health Savings Account (HSA)?

A Health Savings Account (HSA) is a tax-advantaged account for medical expenses, available to anyone enrolled in a qualifying high-deductible health plan (HDHP). It is the only account in the US tax code that is untaxed at all three stages: contributions are deductible, growth is tax-free, and withdrawals for qualified medical expenses are tax-free.

That triple advantage makes an HSA unusual. A traditional 401(k) gives you a deduction now and taxes withdrawals later; a Roth gives you tax-free withdrawals but no deduction. An HSA gives you both.

2026 Contribution Limits

The age-55 catch-up is a flat $1,000 and is not indexed for inflation. If both spouses are 55 or older, each needs their own HSA to claim it, since the catch-up is per person rather than per account.

Contribution limits and the HDHP deductible and out-of-pocket thresholds that determine eligibility are adjusted annually. Confirm current figures before contributing, since exceeding the limit triggers a penalty for each year the excess remains.

Eligibility

You must be enrolled in a qualifying HDHP and cannot:

• Be enrolled in Medicare (this catches people at 65 and is the most common disqualifier)
• Be claimed as a dependent on someone else’s return
• Have other disqualifying coverage, including a general-purpose health FSA, including a spouse’s

You can still contribute if you have a limited-purpose FSA covering only dental and vision.

Medicare enrollment ends contributions permanently. If you enroll mid-year, your contribution limit is prorated by the months you were eligible. Enrolling in Medicare Part A is also retroactive up to six months when you claim Social Security after 65, which can create excess contributions you have to unwind. Anyone working past 65 with an HSA should map this out before claiming benefits.

The Retirement Account Nobody Calls a Retirement Account

The feature that makes an HSA powerful is often missed: there is no deadline to reimburse yourself.

You can pay a medical expense out of pocket today, keep the receipt, leave the money invested for twenty years, and reimburse yourself tax-free later. Nothing requires you to withdraw in the year the expense occurred, as long as the expense came after you opened the account. In effect this converts an HSA into a Roth-like account with a paper trail.

After age 65, non-medical withdrawals are permitted and taxed as ordinary income with no penalty, which makes an HSA behave like a traditional IRA at worst. Before 65, non-qualified withdrawals are taxed and carry a 20% penalty.

HSAs also have no required minimum distributions, unlike traditional IRAs and 401(k)s, so the balance can compound for as long as you like.

The practical implication is that if your cash flow allows, paying current medical costs out of pocket and leaving the HSA invested is usually the higher-value approach. Most providers allow investment above a small cash minimum, and an HSA left in cash for decades forfeits most of the benefit.

Where an HSA fits relative to your other accounts depends on your bracket now, your expected retirement bracket, and whether you can cover medical costs without touching it. Comparing that against your other tax-advantaged space in ProjectionLab’s tax analytics shows what the triple advantage is actually worth over a full career.

HSA vs. FSA

The rollover difference is the one that matters. An FSA forces you to spend within the plan year; an HSA balance is yours permanently and can be invested.

Frequently Asked Questions

Who qualifies for an HSA? Anyone enrolled in a qualifying high-deductible health plan who is not on Medicare, not claimed as a dependent, and has no other disqualifying coverage such as a general-purpose FSA.

What can I spend HSA money on? Qualified medical expenses including deductibles, copays, prescriptions, dental, and vision. Insurance premiums generally do not qualify, with exceptions for COBRA, long-term care premiums, and Medicare premiums after 65.

What happens to my HSA when I turn 65? Contributions must stop once you enroll in Medicare, but the balance stays yours. Qualified medical withdrawals remain tax-free, and non-medical withdrawals become penalty-free while still taxed as income.

Can I invest my HSA? Most providers allow investing above a cash threshold. Leaving an HSA entirely in cash for decades gives up most of the tax-free growth that makes the account valuable.

What happens to my HSA if I change jobs? Nothing. The account is yours, not your employer’s. You can keep contributing as long as you remain covered by a qualifying HDHP.

Should I use my HSA now or save the receipts? If you can pay current expenses from cash flow, leaving the balance invested and reimbursing yourself later usually produces more, since there is no deadline for reimbursement. This only works if you keep documentation.