A Health Savings Account (HSA) is a tax-advantaged account that lets you set aside money specifically for medical expenses. You contribute pre-tax dollars, the balance grows tax-free, and withdrawals for qualified medical costs are also tax-free. To open one, you need to be enrolled in a high-deductible health plan (HDHP), which is typically offered through your employer during open enrollment. Here’s how the whole system works in practice.
Eligibility: The Health Plan Requirement
You can only contribute to an HSA if your health insurance qualifies as a high-deductible health plan. The IRS sets specific thresholds each year. For 2026, an HDHP must have an annual deductible of at least $1,700 for individual coverage or $3,400 for family coverage. Out-of-pocket maximums can’t exceed $8,500 for individuals or $17,000 for families.
If your employer offers an HDHP option alongside a traditional plan, you’ll choose it during open enrollment. Not every HDHP automatically comes with an HSA, so check whether your employer has partnered with an HSA provider or if you need to open one independently. You also can’t be enrolled in Medicare or claimed as a dependent on someone else’s tax return.
How Money Gets Into Your Account
Most employees fund their HSA through payroll deductions. You choose a per-paycheck amount during enrollment, and that money comes out before taxes are calculated. This is an important detail: payroll deductions reduce not only your income tax but also your Social Security and Medicare (FICA) taxes. If you contribute outside of payroll, say through a bank transfer, you can deduct the amount on your tax return, but you won’t recapture those FICA savings.
Your employer may also contribute to your HSA. According to KFF’s 2024 employer benefits survey, the average employer contribution is $705 per year for single coverage and $1,297 for family coverage. That said, roughly a third of employers offering HSA-qualified plans don’t contribute anything, so it varies. When employers do contribute, the average jumps to $842 for single and $1,539 for family coverage. Employer contributions count toward your annual limit, so factor them in when deciding your own contribution amount.
Annual Contribution Limits
The IRS caps how much you and your employer can put into an HSA combined each year. These limits are adjusted annually for inflation. If you’re 55 or older, you can contribute an additional $1,000 per year as a catch-up contribution. Exceeding the limit triggers a 6% excise tax on the excess amount for every year it stays in the account, so it’s worth tracking your contributions carefully, especially if you switch jobs mid-year and have two employers contributing.
The Triple Tax Advantage
HSAs are one of the only accounts in the U.S. tax code that offer benefits at every stage: going in, growing, and coming out.
- Contributions are pre-tax. Every dollar you put in reduces your taxable income for the year. If you’re in the 22% tax bracket and contribute $3,000, that’s $660 less in federal income tax, plus the FICA savings from payroll deductions.
- Growth is tax-free. Any interest or investment returns your balance earns are never taxed, as long as the money stays in the account.
- Withdrawals for medical expenses are tax-free. When you use the funds for qualified costs, you pay zero tax on the distribution.
No other account, not a 401(k), not a Roth IRA, offers tax-free treatment at all three stages. A 401(k) is taxed on withdrawal. A Roth IRA is funded with after-tax dollars. An HSA avoids tax at every step, which is why financial planners often call it the most tax-efficient account available.
What You Can Spend HSA Funds On
HSA money can be used for a broad range of medical, dental, and vision expenses. The IRS defines qualified medical expenses as costs related to the diagnosis, cure, treatment, or prevention of disease. In practical terms, that covers doctor visits, annual physicals, lab work, surgery, ambulance services, psychiatric care, and even transportation to medical appointments like bus or taxi fares.
Dental expenses include cleanings, X-rays, fillings, braces, extractions, and dentures. Vision expenses cover eye exams, glasses, contact lenses (including saline solution), and corrective procedures like LASIK. Prescribed medications and insulin are eligible. Over-the-counter drugs generally aren’t covered unless prescribed by a doctor, with insulin being the exception.
If you use HSA funds for something that doesn’t qualify, you’ll owe income tax on the withdrawal plus a 20% penalty. Keep your receipts. Most HSA providers have apps that let you upload documentation, which makes tracking easier if you’re ever audited.
Investing Your HSA Balance
Most people use their HSA as a checking account for medical bills, but the real long-term power comes from investing. Many HSA providers offer mutual funds, index funds, or target-date funds once your cash balance reaches a minimum threshold, often around $1,000. Any amount above that minimum can be transferred into investments.
This is where the tax-free growth becomes significant. If you can afford to pay current medical expenses out of pocket and let your HSA balance grow in invested funds over 10, 20, or 30 years, the compounding effect is substantial. There’s no requirement to spend HSA money in the year you earn it, and there’s no deadline for reimbursing yourself. You could pay for an expense today, save the receipt, and reimburse yourself from your HSA years later, letting the money grow in the meantime.
HSA Funds Roll Over and Stay Yours
Unlike a Flexible Spending Account (FSA), which generally requires you to spend your balance within the plan year or risk losing it, HSA funds roll over indefinitely. There is no use-it-or-lose-it rule. Your balance carries forward year after year, and the account belongs to you personally, not your employer. If you switch jobs, get laid off, or retire, the money goes with you.
This portability is a major practical difference. An FSA is tied to your employer, and most plans only allow a small carryover or a short grace period. An HSA functions more like a personal savings account that happens to have exceptional tax benefits.
How HSAs Work After Age 65
Once you turn 65, the 20% penalty for non-medical withdrawals disappears. You’ll still owe regular income tax on non-medical withdrawals, making the account function like a traditional 401(k) at that point. For medical expenses, withdrawals remain completely tax-free regardless of your age.
There’s one important timing issue with Medicare. Once you enroll in Medicare, you can no longer contribute to an HSA. If you’re still working past 65 and plan to apply for Social Security or Medicare, you and your employer should stop HSA contributions six months before you enroll. Medicare Part A can be applied retroactively up to six months, which means contributions made during that window could trigger a tax penalty. You can still spend existing HSA funds after enrolling in Medicare; you just can’t add new money.
This makes the HSA a powerful retirement planning tool. If you build up a substantial balance during your working years, you’ll have a tax-free pool of money to cover Medicare premiums, prescription costs, dental work, hearing aids, and other health expenses that tend to increase with age.
What Happens at Tax Time
If your contributions come through payroll, most of the tax work is already done. Your W-2 will show your HSA contributions in Box 12, and your taxable income will already reflect the deduction. You’ll file Form 8889 with your tax return to report contributions and any distributions. If you contributed outside of payroll, you’ll claim the deduction on that form.
Your HSA provider will send you a Form 1099-SA if you took any distributions during the year, and a Form 5498-SA showing your total contributions. Keep records of what you spent HSA money on, even though you don’t need to submit receipts with your return. The IRS can ask for proof that distributions were used for qualified expenses.