What a health care FSA is and how the money moves

A health care Flexible Spending Account (FSA) is a workplace account where you set aside pre-tax dollars to pay for medical expenses. You decide how much to contribute each year, your employer deducts that amount from your paychecks before taxes are calculated, and you use a debit card or submit receipts to withdraw the money when you need it for covered medical costs.

The money belongs to you from the moment it enters the account, but there is a catch: you must spend it within the plan year or lose what remains. Most plans run January through December, though some employers use different calendar years. This is the core trade-off of an FSA—lower taxes now, but strict use-it-or-lose-it rules.

An FSA is separate from health insurance. It does not replace your insurance plan; it works alongside it to help you cover out-of-pocket costs that insurance does not pay for, such as copays, deductibles, coinsurance, and certain medical supplies and services.

Key Takeaways

  • You contribute pre-tax dollars to an FSA through payroll deduction, which lowers your taxable income and the taxes you owe.
  • Money left unspent at the end of the plan year is forfeited; you cannot roll it over to the next year or cash it out.
  • FSAs cover copays, deductibles, coinsurance, prescription drugs, dental work, vision care, and many medical supplies, but not insurance premiums or cosmetic procedures.
  • You access FSA funds using a debit card issued by your plan administrator, or by paying out of pocket and submitting receipts for reimbursement.
  • You can only enroll in or change your FSA contribution during your employer's open enrollment period, or if you have a may have access to life event such as marriage, birth, or loss of coverage.

How much you can contribute and tax savings

The IRS sets an annual limit on how much you can put into a health care FSA. For 2024, that limit is $3,200; for 2025, it is $3,300. Your employer may set a lower limit, so check your plan documents. You choose your contribution amount during open enrollment, and that amount is locked in for the entire plan year unless you have a may have access to life event.

The tax savings come from the fact that FSA contributions are deducted from your paycheck before federal income tax, Social Security tax, and Medicare tax are calculated. If you contribute $2,000 to an FSA and you are in the 22% federal tax bracket, you save roughly $440 in federal taxes alone, plus additional savings from Social Security and Medicare taxes. That is real money back in your pocket.

However, the savings only matter if you actually spend the money. If you contribute $2,000 and spend only $1,200, you lose the remaining $800 when the plan year ends. This is why estimating your medical expenses carefully is important.

What expenses an FSA covers

An FSA covers a broad range of medical, dental, and vision expenses. Copays and coinsurance (your share of the cost after insurance pays) are covered. Deductibles are covered. Prescription drugs, including over-the-counter medications like pain relievers and allergy medicine, are covered if you have a prescription or a doctor's note. Dental work such as cleanings, fillings, and orthodontia is covered. Vision care including eye exams, glasses, and contact lenses is covered.

Medical supplies and equipment are covered too: bandages, crutches, hearing aids, blood glucose monitors, and many other items. Mental health services, physical therapy, and chiropractic care are covered if a doctor orders them. Fertility treatments and certain procedures related to family planning are covered in most plans.

What is not covered: health insurance premiums (your monthly insurance payment), cosmetic procedures, over-the-counter items without a prescription (with some exceptions for certain items like menstrual products), and expenses for a spouse or dependent who is not claimed on your tax return. Gym memberships and weight-loss programs are not covered unless they are prescribed by a doctor for a specific medical condition.

The use-it-or-lose-it rule and the grace period

Money left in your FSA at the end of the plan year does not roll over to the next year. If you do not spend it, you lose it. This is called the use-it-or-lose-it rule, and it is set by federal law. There is no exception, no carryover, and no way to cash out unspent funds.

Some employers offer a grace period of up to 2.5 months after the plan year ends. During this grace period, you can still submit claims for expenses you incurred during the plan year. For example, if your plan year ends December 31 and your employer offers a grace period, you might have until March 15 to submit receipts for medical expenses from January through December. The grace period gives you time to gather receipts and file claims, but it does not extend the deadline for spending the money itself.

A smaller number of employers offer a carryover option that allows you to roll up to $640 (for 2024) into the next plan year. Ask your plan administrator whether your employer offers this; if they do, it changes your strategy for how much to contribute.

How to access and use FSA funds

Most FSA plans issue a debit card that you can use at pharmacies, doctors' offices, and other medical providers. When you swipe the card, the transaction is deducted from your FSA balance. Some cards require you to submit a receipt afterward to prove the expense was may be able to access; others do not. Check your plan documents or call your plan administrator to understand what documentation your card requires.

If your plan does not issue a debit card, or if you prefer to pay out of pocket, you can submit receipts for reimbursement. You pay for the medical expense yourself, then send the receipt and a reimbursement request form to your plan administrator. They review the claim and send you a check or direct deposit within a set timeframe, usually 5 to 10 business days.

Keep all receipts and explanation of benefits (EOB) statements from your insurance. If your plan administrator questions whether an expense is covered, you will need proof that you incurred it and that it qualifies. The IRS can also audit FSA claims, so documentation matters.

FSA enrollment and life changes

You can only enroll in an FSA or change your contribution amount during your employer's open enrollment period, which typically happens once a year in the fall for coverage starting January 1. If you miss open enrollment, you are locked into your current election (or no FSA at all) for the entire year.

A may have access to life event allows you to change your FSA contribution outside of open enrollment. These events include marriage, divorce, birth or adoption of a child, loss of health coverage, a significant change in your spouse's health plan, or a change in your dependent care needs. You typically have 30 to 60 days from the event to notify your employer and make changes. The change takes effect the month after you submit the request.

If you leave your job, your FSA coverage usually ends on your last day of employment. You have a limited window (often 60 days) to submit any remaining claims for expenses you incurred while employed. Unused funds are forfeited; you cannot take them with you or roll them into a new employer's FSA.

FSA versus HSA: when to choose each

An FSA and a Health Savings Account (HSA) are both tax-advantaged accounts for medical expenses, but they work differently. An FSA is available to anyone with a health plan; an HSA is only available if you have a high-deductible health plan (HDHP). An FSA has a use-it-or-lose-it rule; an HSA lets you roll over unused money year after year and even invest it. An FSA contribution limit is $3,300 for 2025; an HSA limit is $4,150 for individual coverage and $8,300 for family coverage.

If your employer offers both an FSA and an HSA, you cannot contribute to both in the same year—federal law prohibits it. If you have an HDHP and expect to have significant medical expenses this year, an FSA might make sense because you can contribute more and access the money immediately. If you have an HDHP and expect low medical expenses, an HSA is usually better because you can save the money for future years or retirement.

If you do not have an HDHP, an FSA is your only option between the two. Compare your expected medical expenses for the year against the contribution limit and the use-it-or-lose-it rule to decide whether contributing to an FSA makes financial sense.

Frequently Asked Questions

Can I use my FSA debit card at any store?

No. FSA debit cards are restricted to medical, dental, and vision merchants. You cannot use them at grocery stores, pharmacies for non-medical items, or general retailers. Some pharmacies allow FSA cards only for prescription drugs and certain medical supplies, not for food or household items. If you try to use the card for an ineligible purchase, the transaction will be declined.

What happens to my FSA if I get fired or laid off?

Your FSA coverage ends on your last day of employment. You have a limited time window (usually 60 days) to submit claims for medical expenses you incurred while employed. Any money left in the account after that deadline is forfeited. You cannot take the balance with you or transfer it to a new employer's plan. If you are laid off and lose health coverage, you may be able to enroll in a new FSA through a new employer or through COBRA, but that is a separate account.

Can I change my FSA contribution mid-year?

Only if you have a may have access to life event such as marriage, birth, adoption, divorce, loss of coverage, or a significant change in your spouse's plan. You cannot change your contribution simply because you want to spend less or more. If you realize mid-year that you chose the wrong amount, you are stuck with that election until the next open enrollment period.

Do I pay taxes on FSA reimbursements?

No. FSA reimbursements are not taxable income. You already received the tax benefit when the money was deducted from your paycheck before taxes were calculated. When you withdraw the money to pay for may be able to access medical expenses, you do not owe taxes on it.

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

Yes, if your spouse is claimed as a dependent on your tax return. You can also use FSA funds for your children's medical expenses if they are dependents. However, you cannot use FSA funds for a spouse or dependent who is not claimed on your tax return, or for an adult child over age 26 (unless they meet specific criteria).