What flexible spending actually does

A flexible spending account (FSA) is a workplace benefit that lets you set aside money from your paycheck before taxes are taken out, then use that money to pay for medical expenses. The key advantage: you avoid federal income tax, Social Security tax, and Medicare tax on the money you contribute. If you set aside $2,500 a year for medical costs, you pay taxes on $2,500 less of your income.

Your employer holds the money in an account. You pay for may be able to access medical expenses out of pocket, then request reimbursement from the account, or you use a debit card tied to the account at the point of sale. The money comes back to you tax-free, which is the entire reason to use one.

FSAs are different from health insurance. They do not cover the cost of insurance premiums themselves, and they do not replace your health plan. They are a way to reduce the tax burden on money you are already spending on medical care.

Key Takeaways

  • Money you contribute to an FSA is not subject to federal income tax, Social Security tax, or Medicare tax, which reduces your taxable income for the year.
  • You can use FSA funds to pay for a wide range of medical expenses including deductibles, copays, prescriptions, dental work, and vision care.
  • FSAs are offered through your employer and are only available if your workplace provides them; you cannot open one on your own.
  • Any money left in your FSA at the end of the year is forfeited — you cannot roll it over to the next year or take it with you if you leave your job.
  • You must enroll during your employer's open enrollment period, which typically happens once a year, and your choice locks in for the full year.

How much you can contribute and when

The IRS sets an annual limit on how much you can contribute to an FSA. That limit changes each year. For 2024, the maximum is $3,200; for 2025, it is $3,300. Your employer may set a lower limit, but cannot allow you to contribute more than the IRS maximum.

You choose your contribution amount during your employer's open enrollment period, which usually happens once a year in the fall or early winter. That amount is deducted from your paycheck in equal installments throughout the year. Once you make your choice, you cannot change it unless you experience a may have access to life event — marriage, divorce, birth of a child, loss of health coverage, or a significant change in your health care costs. A simple change of mind does not may have access to.

If you leave your job, your FSA ends. Any remaining balance stays with your former employer's plan; you cannot transfer it to a new job or take it with you.

What medical expenses you can pay for

FSA funds cover a broad range of medical, dental, and vision expenses. may be able to access expenses include health insurance deductibles and copays, prescription medications, dental work (fillings, crowns, orthodontia), vision care (glasses, contacts, exams), hearing aids, and over-the-counter medications like pain relievers and allergy medicine (though you need a prescription or doctor's note for some OTC items). Physical therapy, mental health counseling, and chiropractic care are also covered.

Expenses that do not may have access to include cosmetic procedures, gym memberships, vitamins without a medical condition diagnosis, and most toiletries. If you are unsure whether a specific expense is may be able to access, your FSA plan administrator can tell you before you spend the money.

You pay for the expense yourself first, then submit a receipt or explanation of benefits to your FSA administrator to request reimbursement. Many FSAs now issue a debit card that you can use directly at pharmacies and medical offices, which skips the reimbursement step.

The use-it-or-lose-it rule and how it works

Money left in your FSA at the end of the calendar year does not roll over to the next year. If you contribute $2,500 and spend only $2,000, the remaining $500 is forfeited — you lose it. This is called the use-it-or-lose-it rule, and it is a hard deadline. There is no way to recover that money or transfer it elsewhere.

Because of this rule, you need to estimate carefully how much medical spending you will actually have in the coming year. Overestimate and you risk losing money. Underestimate and you pay taxes on expenses you could have covered tax-free. Most people who use FSAs contribute a conservative amount based on predictable expenses like copays and prescriptions, rather than trying to max out the limit.

There is a small grace period: your employer may allow you to carry over up to $610 (for 2025) into the next year, or may offer a two-month grace period to spend down your balance. Not all employers offer either option, so check your plan documents.

FSA versus HSA: which one you might have

If your employer offers both an FSA and a health savings account (HSA), you cannot use both in the same year. You must choose one. The main difference: HSA money rolls over year to year and belongs to you even if you leave your job, while FSA money is use-it-or-lose-it and stays with your employer.

HSAs are only available if you are enrolled in a high-deductible health plan (HDHP). FSAs work with any health plan. If your plan qualifies for an HSA, you have a choice. If it does not, an FSA may be your only option for tax-advantaged medical spending.

An HSA is generally better if you expect to have low medical costs and want to save money long-term. An FSA is better if you have predictable annual expenses and want to reduce your taxes this year. Neither is inherently superior — it depends on your situation and your plan options.

How to enroll and what happens if you miss the window

You enroll in an FSA during your employer's open enrollment period by completing a form or using your employer's benefits portal. You will be asked to estimate your medical expenses for the coming year and choose your contribution amount. That choice is binding for the full year.

If you miss open enrollment, you cannot enroll in an FSA until the next open enrollment period — unless you experience a may have access to life event. Getting married, having a baby, losing other health coverage, or a significant change in your spouse's employment can trigger a special enrollment window. You will need to provide documentation of the event.

New employees sometimes get a separate enrollment window when they start a job, even outside the main open enrollment period. Check with your HR department about timing if you are new to your employer.

What to do with receipts and how reimbursement works

Keep receipts for all FSA-may be able to access expenses. When you request reimbursement, your FSA administrator will ask for proof that you paid for an may be able to access expense. This might be an itemized receipt from a pharmacy, a bill from your dentist, or an explanation of benefits from your insurance company.

If you use an FSA debit card, you do not always need to submit receipts upfront — the card is pre-approved for may be able to access expenses at participating vendors. However, your administrator may ask for receipts later to verify that charges were legitimate. Keep them for at least three years.

Reimbursement typically takes one to two weeks after you submit your request. Some employers process it faster. If you need the money quickly, ask your plan administrator about their timeline.

Frequently Asked Questions

Can I use my FSA for my spouse or children?

Yes. FSA funds can pay for may be able to access medical expenses for you, your spouse, and any dependent children, regardless of whether they are covered under your health insurance. You do not need to be the person receiving the care to use FSA money to pay for it.

What happens to my FSA if I quit my job?

Your FSA ends immediately. Any remaining balance is forfeited and does not transfer to your new employer. You may be able to continue coverage through COBRA, which would let you access your remaining balance, but you would pay the full premium yourself. Check with your former employer's HR department about COBRA options.

Can I change my FSA contribution amount mid-year?

Only if you have a may have access to life event such as marriage, divorce, birth of a child, or a significant change in your health coverage. A simple change of mind or a change in your medical spending does not may have access to. If you do have a may have access to event, you usually have 30 to 60 days to make changes.

Are prescription glasses and contacts covered by FSA?

Yes. Eyeglasses, contact lenses, and eye exams are all may be able to access FSA expenses. You can also use FSA funds for laser vision correction (LASIK) and other vision procedures. Keep your receipts from the optometrist or ophthalmologist.

What if I do not spend all my FSA money by the end of the year?

The unused balance is forfeited. Some employers offer a grace period (usually two months into the next year) to spend down your balance, or allow you to carry over up to $610 to the next year. Check your plan documents to see if either option is available. If not, you lose the money.