HSA and FSA are two separate accounts that let you set aside pre-tax money for medical costs, but they have different rules about who can use them, how much you can save, and what happens to unused money.

An HSA (Health Savings Account) is a tax-advantaged savings account tied to a high-deductible health plan. You contribute pre-tax dollars, the money grows tax-free, and you withdraw it tax-free for may have access to medical expenses. Unused money stays in the account and rolls over year to year — it is yours to keep.

An FSA (Flexible Spending Account) is an employer-sponsored account where you set aside pre-tax money for medical or dependent care costs. You contribute through payroll deductions, and the money is available immediately. The catch: most FSAs operate on a "use it or lose it" rule, meaning money you do not spend by the end of the plan year is forfeited.

Both reduce your taxable income and let you pay for medical care without paying income tax on that money. The choice between them depends on your health plan type, how predictable your medical costs are, and whether you want to build long-term savings.

Key Takeaways

  • HSAs require enrollment in a high-deductible health plan and let you keep unused money indefinitely, making them a long-term savings tool.
  • FSAs are employer-run accounts with a use-it-or-lose-it structure, so unspent money typically disappears at year-end.
  • HSA contributions are made by you or your employer; FSA contributions come from your paycheck through payroll deduction.
  • Both accounts use pre-tax dollars, lowering your taxable income and the amount you owe in federal income tax.
  • You can have an FSA and an HSA at the same time if your FSA is limited to dependent care only.

Who Can Open an HSA vs. an FSA

To open an HSA, you must be enrolled in a high-deductible health plan (HDHP). The IRS sets the minimum deductible each year — for 2024, that is $1,600 for individual coverage and $3,200 for family coverage. You cannot have an HSA if you are covered by any other health insurance, are enrolled in Medicare, or are claimed as a dependent on someone else's tax return.

An FSA is available only through your employer's benefits plan. Your employer sets up the account structure and decides what expenses it covers. You enroll during your company's open enrollment period, usually once a year. Unlike an HSA, there is no income limit or health plan requirement — you can have an FSA with any type of health insurance.

If your employer offers both, you can have both accounts at the same time, but only if your FSA is limited to dependent care expenses (childcare or adult care). You cannot have a medical FSA and an HSA in the same year.

Contribution Limits and How Money Gets In

HSA contribution limits are set by the IRS and change annually. For 2024, you can contribute up to $4,150 for individual coverage or $8,300 for family coverage. You can contribute through payroll deduction, a direct deposit from your bank, or a check. If you are 55 or older, you can add an extra $1,000 per year as a catch-up contribution. Your employer may also contribute to your HSA, and that money counts toward your limit.

FSA contribution limits are also set by the IRS — for 2024, the maximum is $3,300 per year for a medical FSA or dependent care FSA. Money goes in through payroll deduction only; your employer cannot contribute to an FSA on your behalf. You decide how much to contribute during open enrollment, and that amount is deducted from each paycheck throughout the year.

With an HSA, you control the contribution amount and can change it if your circumstances change (marriage, birth of a child, loss of coverage). With an FSA, you are locked in for the plan year unless you have a may have access to life event.

What Happens to Money You Do Not Spend

This is the biggest difference between the two accounts. HSA money that you do not spend stays in your account forever. It earns interest or investment returns (depending on how you invest it), and you can withdraw it tax-free for medical expenses at any point in your life. If you reach retirement age, you can withdraw HSA money for any reason without penalty, though non-medical withdrawals are taxed as income.

FSA money operates under a use-it-or-lose-it rule. Any balance remaining in your FSA at the end of the plan year is forfeited and goes back to your employer. However, employers can offer a grace period (up to 2.5 months into the next year) to spend remaining funds, or they can allow a $640 carryover into the next year. Your employer chooses which option to offer, so check your plan documents to see what applies to you.

Because of this rule, FSA users need to estimate their medical costs carefully. Overestimate and you lose money; underestimate and you pay out of pocket. HSA users do not face this pressure — they can contribute conservatively and let the account grow.

What You Can Buy With Each Account

Both accounts cover the same range of may have access to medical expenses: copays, coinsurance, deductibles, prescription drugs, dental work, vision care, mental health treatment, and many over-the-counter items like pain relievers and first-aid supplies. The IRS publishes a full list of may have access to expenses, and both accounts follow the same rules.

FSAs can also cover dependent care expenses — childcare, preschool, or adult day care — if your employer offers a dependent care FSA. HSAs cannot be used for dependent care.

Both accounts have the same restriction: you cannot use the money for health insurance premiums (with narrow exceptions for COBRA, Medicare, or long-term care insurance). You also cannot use either account for cosmetic procedures or over-the-counter items that are not medical in nature.

Tax Advantages and How They Work

Both HSAs and FSAs reduce your federal income tax. Money you contribute does not count as taxable income, so your taxable income is lower. If you contribute $3,000 to an FSA and you are in the 22% tax bracket, you save $660 in federal income tax. You also avoid paying Social Security and Medicare taxes on that money, which saves an additional 7.65%.

With an HSA, the tax advantage is even stronger because the money can grow tax-free and be withdrawn tax-free. If you invest your HSA balance and it earns $500 in returns, that growth is not taxed. With an FSA, any interest earned is minimal because the money is typically held in a non-interest-bearing account.

Both accounts reduce your taxable income at the federal level. Some states also exclude HSA and FSA contributions from state income tax, though a few states tax HSA withdrawals. Check your state's rules if you live in a state with income tax.

Which Account Makes Sense for Your Situation

Choose an HSA if you are enrolled in a high-deductible health plan and want to build long-term savings for medical costs. HSAs work best if you have predictable medical expenses or if you can afford to pay medical bills out of pocket and let the HSA grow. An HSA is also valuable if you are healthy and do not expect large medical costs — you can invest the money and use it in retirement.

Choose an FSA if your employer offers one and you have predictable annual medical or dependent care costs that you know you will spend. FSAs work best if you have regular expenses like copays, prescriptions, or childcare that you can estimate accurately. An FSA is also useful if you want to lower your taxable income in a specific year.

If your employer offers both and you are may be able to access for an HSA, many financial advisors recommend maximizing the HSA first because of its long-term savings potential and the lack of a use-it-or-lose-it rule. You can then use an FSA for dependent care if needed.

Frequently Asked Questions

Can I use my HSA or FSA to pay for my spouse's medical expenses?

Yes. Both accounts can pay for medical expenses of you, your spouse, and your dependents — even if they are not covered under your health plan. The expense must be may have access to and incurred by someone you can claim as a dependent on your tax return (or your spouse, regardless of dependent status).

What happens to my HSA if I change jobs?

Your HSA stays with you. It is your personal account, not tied to your employer. You can take it to a new job, keep it with the same bank or provider, or roll it into a new HSA. Your FSA, however, is employer-owned and ends when you leave the job — you typically have a short window to spend remaining funds or lose them.

Can I withdraw money from my HSA or FSA for non-medical reasons?

With an FSA, no — non-medical withdrawals are not allowed. With an HSA, you can withdraw money for any reason, but non-medical withdrawals are taxed as income and subject to a 20% penalty if you are under 65. After age 65, you can withdraw for any reason without penalty, though non-medical withdrawals are still taxed as income.

Do I have to use my HSA or FSA debit card, or can I pay out of pocket and reimburse myself?

Both accounts allow you to pay out of pocket and reimburse yourself later. You do not have to use a debit card. Keep your receipts as proof of the expense — the IRS can ask for documentation if you are audited.

What if my employer does not offer an HSA or FSA?

If you have a high-deductible health plan, you can open an HSA on your own through a bank or financial institution — you do not need your employer to offer one. If your employer does not offer an FSA, you cannot open one independently; FSAs are employer-sponsored only.