HSA vs. FSA: What's the Difference, and Which One Should You Use?

Short answer: The main HSA vs. FSA difference is ownership. A Health Savings Account (HSA) is yours: the money rolls over every year, stays with you when you change jobs and can grow tax-free, but you need a high-deductible health plan to contribute. A health Flexible Spending Account (FSA) is an employer benefit that works with most health plans and gives you the full year's amount up front, but money you don't spend is generally lost. For 2026, you can put up to $4,400 (self-only) or $8,750 (family) in an HSA and up to $3,400 in a health FSA.

What Is the Difference Between an HSA and an FSA?

Both accounts let you pay for medical costs with money that isn't taxed. The rules around who can open one, how much you can put in and what happens to leftover money are very different.

	HSA	Health FSA
Who owns it	You	Your employer's plan
Health plan required	High-deductible health plan (HDHP); bronze and catastrophic plans also count starting 2026	None; most employer plans
2026 contribution limit	$4,400 self-only / $8,750 family	$3,400 per employee
2027 contribution limit	$4,500 self-only / $9,000 family	Not yet announced when we updated this guide
Age 55+ catch-up	Extra $1,000	None
Leftover money	Carries over every year	Generally lost; plan may allow a carryover (up to $680 for 2026) or a grace period of up to 2½ months
When money is available	As you contribute	Full annual amount from the start of the plan year
Investment earnings	Not taxed while held in the account	Not applicable
If you change jobs	Account goes with you	Tied to your employer's plan

All figures are from the IRS.

How Does an HSA Work?

An HSA is a tax-advantaged account you own, paired with a qualifying health plan. The IRS describes several tax benefits:

• Contributions you make are deductible, and contributions your employer makes aren't included in your income.
• Earnings in the account aren't taxed while they stay there.
• Withdrawals for qualified medical expenses aren't taxed.
• Money left at the end of the year carries over, and the account is portable if you change employers or leave the workforce.

Who can contribute. To be eligible, you must:

1. Be covered by an HDHP on the first day of the month.
2. Have no other health coverage, except types the IRS allows.
3. Not be enrolled in Medicare.
4. Not be claimed as a dependent on someone else's tax return.

What counts as an HDHP. For 2026, the plan's deductible must be at least $1,700 for self-only coverage or $3,400 for family coverage, and out-of-pocket costs can't exceed $8,500 or $17,000. For 2027, those figures rise to a $1,750 or $3,500 minimum deductible and an $8,700 or $17,400 out-of-pocket maximum.

What changed in 2026. The One, Big, Beautiful Bill expanded who can use an HSA. Starting January 1, 2026, bronze and catastrophic plans available through an Exchange are treated as HSA-compatible, and IRS Notice 2026-05 says they don't have to be bought through an Exchange to qualify. Also starting in 2026, people in certain direct primary care arrangements can still contribute to an HSA and can use HSA money tax-free for those periodic fees. The law also made permanent the rule that lets you get telehealth care before meeting your deductible without losing HSA eligibility.

How Does a Health FSA Work?

A health FSA is a benefit your employer sets up, usually as part of a cafeteria plan. You agree to have part of your salary go into the account, and your employer may add money too. According to the IRS, you don't pay federal income tax or employment taxes on the salary you contribute.

The limit. For 2026, you can contribute up to $3,400 through salary reductions, up $100 from 2025.

Money up front. Your plan must let you be reimbursed for the full amount you elected at any time during the coverage period, even before you've contributed it. If you elect $2,000 and have a $1,500 procedure in January, the plan can reimburse the full $1,500 right away.

Use it or lose it. Money you don't spend by the end of the plan year is generally forfeited. Your employer can soften this in one of two ways, but not both:

• A grace period of up to 2½ months after the plan year ends to spend the remaining balance.
• A carryover of unused money into the next year, up to $680 for plan years beginning in 2026.

What it can't pay for. FSA money can't be used for health insurance premiums. Self-employed people aren't eligible for FSAs.

Can You Have an HSA and an FSA at the Same Time?

Usually not the standard kind. The IRS says an employee covered by an HDHP and a general-purpose health FSA generally can't make HSA contributions. That catches people out during open enrollment, especially when a spouse signs up for a general-purpose FSA that covers the whole family.

There's a workaround. A limited-purpose FSA pays for items like dental and vision care, and it doesn't block HSA contributions. If your employer offers one, you can use it for predictable dental and vision costs while your HSA balance carries over.

HSA or FSA: Which One Fits Your Situation?

The choice often comes down to which health plan you pick, since an HSA requires a qualifying plan. Once that's settled, these patterns help:

An HSA tends to fit if you:

• Are healthy enough that a high-deductible plan makes sense, or can cover the deductible from savings.
• Want the money to roll over and grow over many years.
• Might change jobs or leave the workforce.
• Want a pool of money for medical costs in retirement.

An FSA tends to fit if you:

• Have a low-deductible plan or a plan that doesn't qualify for an HSA.
• Have predictable yearly costs, such as prescriptions, glasses or braces.
• Want the full annual amount available early in the year.

Some people use both: an HSA with a limited-purpose FSA for dental and vision.

How Does an HSA Help in Retirement?

Because HSA money rolls over and earnings aren't taxed while they stay in the account, some savers treat an HSA as a long-term account for health costs in retirement. A few rules shape how that works:

• Withdrawals for other costs. Money taken out for anything other than qualified medical expenses is taxable and generally owes an additional 20% tax. That additional tax doesn't apply after you turn 65, though the withdrawal is still taxable income.
• Medicare ends new contributions. Once you enroll in Medicare, you're no longer an eligible individual, so you can't add money. You can still spend what's in the account on qualified expenses. Our guide to who qualifies for Medicare and when to sign up explains when enrollment happens, including automatic enrollment for people already getting Social Security.
• Catch-up contributions. If you're 55 or older at the end of the year, you can add $1,000 above the standard limit.

An HSA works alongside, not instead of, your workplace retirement plan. See our guide to 401(k) contribution limits for 2026 and try the retirement savings calculator to see how your overall savings add up.

The Bottom Line

If you have an HSA-eligible plan, an HSA usually offers more flexibility: you own it, it rolls over and it can grow. A health FSA makes sense when you don't have a qualifying plan or you want your full annual amount up front for known costs. Just don't pair an HSA with a general-purpose FSA, and spend down your FSA balance before the deadline your plan sets.

FinancialAdviser.com is not a tax preparer and nothing here is tax advice. Plan rules vary by employer; check your plan documents or ask your benefits administrator.

Frequently asked questions

Can I have both an HSA and an FSA?

Generally not a general-purpose health FSA. The IRS says someone covered by a high-deductible health plan and a general-purpose health FSA generally can't make HSA contributions. You can pair an HSA with a limited-purpose FSA, which covers things like dental and vision care.

What happens to money left in an FSA at the end of the year?

It's generally lost, which is why FSAs are called use-it-or-lose-it. Your employer's plan may offer either a grace period of up to 2½ months after the plan year ends or a carryover of up to $680 of unused money from plan years beginning in 2026, but not both.

What are the HSA contribution limits for 2026 and 2027?

For 2026, $4,400 for self-only coverage and $8,750 for family coverage. For 2027, $4,500 and $9,000. If you're 55 or older at the end of the tax year, you can add $1,000.

Can I use HSA money for non-medical expenses?

Yes, but withdrawals that aren't for qualified medical expenses are taxable and generally owe an additional 20% tax. The additional tax doesn't apply after you turn 65, become disabled or die, though the withdrawal is still taxable income.

Can I keep contributing to my HSA after I enroll in Medicare?

No. The IRS says you can't be enrolled in Medicare and be an eligible individual for HSA contributions. You can keep the account and keep using the money for qualified medical expenses.

Sources

1. IRS Publication 969: Health Savings Accounts and Other Tax-Favored Health Plans
2. IRS: Tax Inflation Adjustments for Tax Year 2026 (IR-2025-103)
3. IRS: Revenue Procedure 2026-24 (2027 HSA Limits)
4. IRS: Guidance on New HSA Tax Benefits Under the One, Big, Beautiful Bill (IR-2025-119)

This guide is general information, not personal advice. Your situation may differ, so consider talking with a qualified professional, such as a fiduciary financial adviser, CPA or licensed agent, before making a decision.