Can You Use Both an HSA and an FSA at the Same Time?

You cannot have both a traditional FSA and an HSA in the same year, with one narrow exception

If you are enrolled in a health savings account (HSA), you cannot also contribute to a standard flexible spending account (FSA) during that same calendar year. The IRS treats this as a violation of HSA rules, and you would lose the tax-advantaged status of your HSA for the entire year.

The one exception is a limited-purpose FSA (also called a restricted FSA), which covers only dental and vision expenses. You can pair this with an HSA because the limited-purpose FSA does not cover medical care, so there is no overlap in what the two accounts can pay for.

A dependent care FSA (for childcare expenses) also works alongside an HSA, since it covers a completely different category of spending. The restriction applies only to medical and general health FSAs.

Key Takeaways

• A standard medical FSA and an HSA cannot both be active in the same tax year; choosing one means you cannot use the other until the following year.
• A limited-purpose FSA for dental and vision only can coexist with an HSA because it does not pay for medical services.
• A dependent care FSA for childcare expenses can run alongside an HSA without conflict.
• If you switch from an FSA to an HSA, you must wait until the next calendar year to enroll, or your HSA loses its tax benefits for that year.
• Unused FSA funds do not roll over to an HSA; money left in an FSA at year-end is forfeited under the use-it-or-lose-it rule.

Why the HSA and FSA conflict exists

Both accounts are designed to let you set aside pre-tax money for health expenses. An HSA requires you to be enrolled in a high-deductible health plan (HDHP), while an FSA works with any health insurance. The IRS rule exists because an FSA lets you access money immediately for any medical expense, which would let you double-dip: use FSA funds for a service, then use HSA funds for the same service or claim it again on your taxes.

The restriction is strict. If you contribute to both in the same year, the IRS will disqualify your HSA retroactively to January 1 of that year. You lose the tax deduction on all HSA contributions, and you owe income tax plus a 20 percent penalty on the earnings your HSA generated. This applies even if you made an honest mistake or did not realize the rule existed.

Your employer's payroll system should prevent you from enrolling in both during open enrollment, but if you change jobs mid-year or enroll in coverage outside open enrollment, the burden falls on you to catch the conflict.

Limited-purpose FSAs: the workaround that actually works

A limited-purpose FSA covers only dental and vision care—cleanings, exams, glasses, contacts, and procedures like root canals or LASIK. It does not cover medical office visits, prescriptions, or any other health services. Because the two accounts cover completely separate categories, the IRS allows both to be active at the same time.

The contribution limits are separate. For 2024, a standard FSA caps out at $3,200 per year (this amount changes annually). A limited-purpose FSA has the same cap, so you could theoretically set aside $3,200 for dental and vision through the FSA and another amount through your HSA for everything else. Check your plan documents, because some employers set lower limits than the IRS maximum.

The limited-purpose FSA still follows the use-it-or-lose-it rule: money you do not spend by December 31 is forfeited. Some plans offer a grace period (usually 2.5 months into the next year) or a carryover of up to $610, but this varies by employer. An HSA, by contrast, rolls over indefinitely, so unused money stays in the account year after year.

Dependent care FSAs work alongside HSAs without restriction

A dependent care FSA (also called a dependent care account or DCA) pays for childcare, preschool, after-school programs, and summer camps—expenses that let you work or look for work. It does not pay for health care, so there is no conflict with an HSA.

The contribution limit for dependent care is much lower: $5,000 per year for married couples filing jointly, or $2,500 for single filers (these limits have not changed since 2013). Like a medical FSA, it follows use-it-or-lose-it rules, though some employers allow a grace period.

You can have an HSA, a limited-purpose FSA for dental and vision, and a dependent care FSA all in the same year. Each account is separate, with its own contribution limit and its own rules about what expenses may have access to.

What happens to FSA money if you switch to an HSA

FSA funds do not transfer to an HSA. If you have money left in an FSA at the end of the year, it is forfeited—you cannot move it to an HSA or carry it forward. This is the use-it-or-lose-it rule, and it applies to almost all FSAs (dependent care FSAs sometimes allow a grace period, but medical FSAs rarely do).

If you are thinking about switching from an FSA to an HSA, plan your FSA spending carefully in the year you make the switch. Estimate your dental, vision, and medical expenses for the rest of the year, and adjust your FSA contribution accordingly. Any balance remaining on December 31 will be lost.

You can enroll in an HSA starting January 1 of the following year. If you try to enroll in both an FSA and an HSA in the same calendar year—even if you time it so the FSA ends before the HSA begins—the IRS will still disqualify your HSA for the entire year.

How to choose between an HSA and a standard FSA

An HSA is usually the better long-term choice if you are may be able to access. You can invest HSA funds like a retirement account, money rolls over indefinitely, and there is no use-it-or-lose-it deadline. You can withdraw funds tax-free for medical expenses at any age, and after age 65, you can withdraw for any reason (you pay income tax but no penalty, similar to a traditional IRA).

An FSA makes sense if you have predictable, near-term health expenses—you know you need glasses this year, or your child needs braces—and you want to use pre-tax money to pay for them. The immediate access and simplicity appeal to some people, but the forfeiture risk is real. If you overestimate your spending and cannot use the full balance, you lose money.

If your employer offers both, compare the plan designs. Some HSA-may be able to access plans have higher deductibles or lower employer contributions than FSA plans. Run the numbers for your family's typical health spending to see which saves more in taxes and out-of-pocket costs.

Mid-year changes and special circumstances

Open enrollment is the normal time to choose between an HSA and an FSA, but life changes can trigger a mid-year switch. If you have a may have access to event—marriage, birth of a child, loss of coverage, or change in employment—you may be able to enroll in coverage outside the annual window.

If you leave an FSA job and start a new job with an HSA-may be able to access plan, you cannot contribute to the HSA until January 1 of the next year. If you try to enroll in the HSA before the calendar year ends, you will trigger the conflict and lose the HSA's tax status for that year.

Some employers offer a FSA-to-HSA bridge or allow you to drain your FSA balance before switching to an HSA mid-year, but this is rare. Check with your new employer's benefits team before you enroll in anything.

Frequently Asked Questions

What happens if I accidentally enroll in both an HSA and an FSA in the same year?

The IRS will disqualify your HSA retroactively to January 1. You lose the tax deduction on all HSA contributions for that year, owe income tax on the money you put in, and pay a 20 percent penalty on any earnings. Contact your employer's benefits team immediately if this happens; some plans have a short window to correct the error before penalties apply.

Can I use my FSA to pay for dental work and my HSA to pay for medical visits?

Only if you have a limited-purpose FSA that covers dental and vision. A standard medical FSA and an HSA cannot both be active in the same year, so you cannot split expenses between them. If you have a limited-purpose FSA, yes—use it for dental and vision, and use your HSA for everything else.

Do I lose my FSA balance if I switch jobs?

Yes, in almost all cases. FSA funds are tied to your employer's plan and do not transfer when you change jobs. You forfeit any unused balance on your last day of coverage. Plan your FSA spending carefully if you know you are leaving a job.

Can I have an HSA and a dependent care FSA at the same time?

Yes. Dependent care FSAs cover childcare and preschool, not health care, so there is no conflict with an HSA. You can have both active in the same year, each with its own contribution limit and rules.

Is a limited-purpose FSA worth it if I already have an HSA?

It depends on your dental and vision costs. If you wear glasses, have regular dental work, or expect major procedures, a limited-purpose FSA lets you set aside additional pre-tax money. If your dental and vision expenses are minimal, the HSA alone may be enough, and the limited-purpose FSA's use-it-or-lose-it rule adds complexity.