If your employer mentioned FSA during open enrollment and you glossed over it, you are not alone. Many workers are uncertain about what are FSA funds and how they differ from their regular health insurance. In simple terms, FSA funds are pre-tax dollars set aside from your paycheck specifically to pay for qualified medical expenses. They reduce your taxable income and can save you 25% to 40% on healthcare costs you are already paying for out of pocket.
According to the Bureau of Labor Statistics, nearly half of workers at companies with 100 or more employees have access to a healthcare FSA. Yet many do not participate, often because they do not fully understand how the money works.
FSA Funds: The Basics
FSA funds are money that your employer withholds from your gross pay before calculating federal income tax, state income tax, Social Security tax, and Medicare tax. The money goes into a special account administered by a third-party benefits company like HealthEquity, WageWorks, or Optum Financial. You then draw from this account throughout the year to pay for eligible healthcare expenses.
The critical concept is the pre-tax treatment. If you earn $60,000 and contribute $3,000 to your FSA, your taxable income drops to $57,000. You still have access to the $3,000 for medical spending, but you never pay income tax or payroll tax on it. The money effectively stretches further than after-tax dollars. For the mechanics of how this works paycheck to paycheck, see our detailed FSA explainer.
Where FSA Funds Come From
You elect your contribution amount during your employer’s annual open enrollment period, typically in the fall for a January 1 plan year start. The 2025 IRS maximum for healthcare FSA contributions is $3,300 per employee. Your employer deducts the amount evenly across your paychecks throughout the year. Some employers also contribute to employee FSAs as part of their benefits package, though this is less common.
Once elected, your contribution amount is generally locked for the plan year. You can only change your election mid-year if you experience a qualifying life event such as marriage, divorce, birth of a child, adoption, or a change in your spouse’s employment status that affects their benefits. Plan your election carefully by estimating your expected out-of-pocket medical costs for the coming year.
What FSA Funds Can Pay For
FSA funds cover a wide range of medical expenses defined by the IRS under Section 213(d) of the Internal Revenue Code. Major categories include medical services like office visits, specialist appointments, lab work, imaging, and hospital stays. Prescription drugs are covered at any pharmacy. Dental services including cleanings, fillings, crowns, orthodontics, and dentures qualify. Vision care including exams, glasses, contact lenses, and laser eye surgery is covered.
Since the CARES Act of 2020, over-the-counter medications no longer require a prescription to be FSA eligible. This includes common products like Tylenol, Advil, Zyrtec, Pepto-Bismol, and cold and flu remedies. Menstrual care products were also permanently added to the eligible expense list. Sunscreen with SPF 15 or higher qualifies as well.
What FSA Funds Cannot Pay For
Certain categories are explicitly excluded. Cosmetic procedures performed solely for appearance, such as teeth whitening, cosmetic surgery, and hair transplants, do not qualify. Health club or gym membership dues are generally not eligible. Insurance premiums, including health insurance and long-term care insurance, cannot be paid with FSA funds. Personal care items like toothbrushes, shampoo, and general-purpose vitamins and supplements taken for overall wellness are excluded.
The gray area comes with items that can serve both medical and personal purposes. Products like air purifiers, mattresses, and special shoes may qualify only when prescribed for a specific medical condition with supporting documentation. When in doubt, check IRS Publication 502 or contact your FSA administrator before making a purchase.
The Use-It-or-Lose-It Rule
The most important thing to understand about what are FSA funds is that they generally do not carry over from year to year. If you do not spend your balance by the end of the plan year, you forfeit the remaining money. Your employer may offer one of two IRS-allowed exceptions: a grace period of up to 2.5 months after the plan year ends, or a carryover provision that lets you roll up to $660 (2025 limit) into the next year. Not all employers offer either option, and no employer can offer both.
This forfeiture rule makes accurate planning essential. Underestimating your FSA election means you miss out on tax savings for expenses you end up paying with after-tax dollars. Overestimating means you either scramble to spend down the balance or lose money outright. Review your previous year’s medical receipts to estimate a realistic election amount.
How to Access Your FSA Funds
Most FSA administrators provide a debit card that links directly to your FSA account. This card works at pharmacies, doctor’s offices, hospitals, dental clinics, and many retailers for eligible purchases. When the card is declined or you pay out of pocket, you can submit a manual reimbursement claim through your administrator’s website or mobile app. Keep receipts and explanations of benefits for all FSA-related expenses in case your administrator requests documentation or the IRS audits your account.
One unique feature of FSA funds is front-loading: your entire annual election is available on the first day of the plan year, even though you have contributed only a fraction through payroll deductions. If you elect $3,300 and need a $2,000 dental procedure in January, you can use your FSA to pay for it immediately. This is different from an HSA, where you can only spend what you have deposited.
Frequently Asked Questions
Are FSA funds taxed?
No. FSA contributions are deducted from your pay before federal, state, Social Security, and Medicare taxes are calculated. Withdrawals for qualified medical expenses are also tax-free. You do not report FSA contributions or reimbursements on your personal tax return. Learn more about the pre-tax nature of FSAs.
Can I use FSA funds for my family?
Yes. FSA funds can cover qualified medical expenses for you, your spouse, and your tax dependents, regardless of whether they are enrolled in your employer’s health plan.
What happens to my FSA if I get fired or quit?
Typically, you lose access to remaining FSA funds when employment ends. You can be reimbursed for eligible expenses incurred before your termination date, but the account is usually closed after that. COBRA continuation for FSAs is available but rarely cost-effective.
How much should I contribute to my FSA?
Base your election on your expected out-of-pocket medical costs for the year. Add up anticipated copays, prescriptions, dental work, vision expenses, and any planned procedures. If you are unsure, start conservative to minimize the risk of forfeiture. You can always increase your election the following year if you find you are paying significant amounts out of pocket.
The Bottom Line
FSA funds are simply your own money, taken from your paycheck before taxes, and earmarked for medical spending. The tax savings are real and meaningful. The trade-off is the use-it-or-lose-it deadline and the requirement to plan ahead. If you have predictable medical expenses — and most people do — an FSA is one of the easiest ways to reduce your tax burden while covering costs you would pay regardless. Understanding what are FSA funds and how to use them effectively is a basic financial literacy skill that pays for itself every year you participate.