How a Flexible Spending Account works

A Flexible Spending Account (FSA) is a tax-advantaged account where you set aside pre-tax money from your paycheck to pay for medical expenses. Your employer deducts the amount you choose directly from your salary before taxes are calculated, which lowers your taxable income for the year. You then use a debit card, reimbursement forms, or direct payment to draw from that account when you have may be able to access medical costs.

The money in your FSA is yours to spend on may have access to medical expenses—copays, deductibles, prescription drugs, dental work, vision care, and many over-the-counter items. You do not have to wait for insurance to process a claim first. If you have the receipt and the expense is FSA-may be able to access, you can pay for it immediately and reimburse yourself from the account.

The main catch is the use-it-or-lose-it rule: any money left in your FSA at the end of the plan year does not roll over to the next year. Most employers allow a grace period of up to 2.5 months into the following year to spend remaining funds, or they offer a carryover of up to $640 (the amount changes annually). Check your employer's plan documents to see which option applies to you.

Key Takeaways

  • You choose how much to contribute to your FSA during open enrollment, and that money is deducted pre-tax from each paycheck throughout the year.
  • You can pay for copays, deductibles, prescriptions, dental, vision, and many over-the-counter medical items directly from your FSA without waiting for insurance approval.
  • Money not spent by the end of the plan year is forfeited unless your employer offers a grace period or carryover option.
  • You need receipts and proof that expenses are FSA-may be able to access; some purchases require a letter from your doctor to may have access to.
  • FSA funds reduce your taxable income, which can save you hundreds of dollars in federal, state, and payroll taxes depending on your income and contribution amount.

When to enroll and how much to contribute

You can only open or change your FSA contribution during your employer's open enrollment period, which typically happens once a year in the fall for coverage starting January 1. If you have a may have access to life event—marriage, divorce, birth of a child, loss of other health coverage—you can make changes outside of open enrollment within 30 to 60 days of the event.

Deciding how much to contribute requires looking at your medical spending from the past year or two. Add up copays, deductibles you actually paid, prescription costs, dental work, glasses or contacts, and any other out-of-pocket medical expenses. That total is a reasonable starting point for your FSA contribution. Most employers allow contributions between $110 and $3,200 per year (the maximum changes annually). If you are unsure, start with a conservative amount—it is easier to increase next year than to lose unspent money.

Remember that FSA money is separate from your health insurance deductible. If you have a high-deductible plan, you might want to contribute enough to cover your deductible plus routine copays and prescriptions. If you have a low-deductible plan with predictable costs, you can estimate more precisely.

Which medical expenses you can pay for with FSA funds

FSA funds cover a wide range of medical costs. Copays and coinsurance for doctor visits, urgent care, and emergency room visits all may have access to. Deductibles you pay out of pocket count. Prescription medications, insulin, and other drugs covered by your insurance are may be able to access. Dental work including cleanings, fillings, root canals, and orthodontia is covered. Vision expenses like eye exams, glasses, contacts, and contact solution are may be able to access.

Over-the-counter items are trickier. Aspirin, antacids, allergy medicine, and cold medicine do not may have access to unless your doctor writes a prescription for them. Bandages, first-aid supplies, and heating pads do may have access to. Sunscreen does not. Pregnancy tests and contraception do may have access to. If you are unsure whether an item is may be able to access, check your FSA plan's list of approved expenses or contact your plan administrator before you buy.

Expenses that do not may have access to include cosmetic procedures, gym memberships, vitamins (unless prescribed by a doctor), and most wellness products. Childcare and dependent care are handled through a separate account called a Dependent Care FSA, not your medical FSA.

How to pay for expenses and get reimbursed

Most FSAs issue a debit card that you can use at pharmacies, doctor offices, and other medical providers. When you swipe the card, the transaction is checked against a database of FSA-may be able to access merchants. If the merchant code matches medical services, the payment usually goes through immediately. Keep your receipt anyway—your plan administrator may ask for proof later that the expense was medical and not personal.

If a merchant does not accept the FSA debit card, you can pay out of pocket with your personal credit card or cash, then submit a reimbursement request. You will need the original receipt, an itemized statement showing what was purchased, and proof that the expense is FSA-may be able to access. Some plans require a letter from your doctor confirming the medical necessity. Submit these documents to your plan administrator through their website, mobile app, or by mail. Reimbursement typically takes 5 to 10 business days.

Keep all receipts and documentation for at least three years. The IRS can audit FSA accounts, and you need proof that every dollar you withdrew was spent on a legitimate medical expense. If you cannot produce a receipt, you may have to repay that amount to the account or face tax penalties.

What happens to unused FSA money

If you have money left in your FSA at the end of the plan year, the outcome depends on your employer's plan design. Some employers offer a grace period of up to 2.5 months into the next year to spend remaining funds—so money left on December 31 can still be used through mid-March. Other employers allow a carryover of up to $640 (adjusted annually) to roll into the next year's account. A few plans offer both, though that is less common.

If your plan offers neither a grace period nor a carryover, any unspent balance is forfeited. This is why estimating your contribution carefully matters. If you contributed $2,000 but only spent $1,200 and your plan has no grace period or carryover, you lose $800. That money goes back to your employer or is used to reduce the cost of the plan for all employees.

You can check your plan documents or ask your HR department which option your employer uses. If you know you will not spend all your FSA money by year-end, you can request a reduction in your contribution for the following year during the next open enrollment.

FSA vs. HSA: which account to use first

If you have both an FSA and a Health Savings Account (HSA), you cannot contribute to both in the same year—the IRS allows one or the other, not both. However, if you already have an HSA from a previous year, you can use it to pay for current medical expenses while contributing to an FSA.

The strategy most people follow is to use FSA funds first because they expire at the end of the year. HSA funds roll over indefinitely and can grow like a retirement account, so it makes sense to preserve them. Pay for immediate medical expenses with your FSA debit card, and save your HSA for future years or major medical costs down the road.

If you are choosing between an FSA and an HSA for the first time, an HSA is usually the better long-term choice because the money does not disappear. But if your employer offers both and you have predictable annual medical costs, an FSA can provide immediate tax savings on money you know you will spend.

Common mistakes and how to avoid them

The biggest mistake is overestimating how much you will spend and losing money to the use-it-or-lose-it rule. Start conservatively—you can always increase your contribution next year. If you are new to an FSA, contribute only what you spent on medical costs in the past 12 months, minus anything your insurance covered.

Another common error is forgetting that the FSA debit card only works at medical merchants. If you try to use it at a grocery store or gas station, it will be declined even if you are buying an FSA-may be able to access item like over-the-counter medicine. Keep a personal payment method handy and submit a reimbursement request instead.

Do not throw away receipts. Many people lose track of documentation and cannot prove their expenses later. Photograph or scan receipts as you go, or keep them in a folder. If your plan administrator asks for proof and you cannot provide it, you may have to repay the money or face tax consequences.

Finally, do not assume an item is FSA-may be able to access just because it is medical-related. Cosmetic procedures, gym memberships, and most over-the-counter items without a prescription are not covered. Check your plan's list before you buy, especially for items you are unsure about.

Frequently Asked Questions

Can I use my FSA debit card at any pharmacy or doctor's office?

Most pharmacies and medical providers accept FSA debit cards, but not all. The card works at merchants with medical service codes. If a pharmacy or office does not accept it, pay out of pocket and submit a reimbursement request with your receipt. Some small practices or independent providers may not have the infrastructure to process FSA cards.

What happens to my FSA if I leave my job?

You typically have until the end of the plan year to spend any remaining FSA balance, even after you leave. After that date, unspent money is forfeited. If you are leaving mid-year, check with your employer's HR department about whether you can continue using the account or if it closes immediately. Some employers allow COBRA continuation for FSA accounts, though it is less common than for health insurance.

Do I need a prescription for over-the-counter medicine to use my FSA?

Most over-the-counter medicines do not may have access to without a prescription. Aspirin, cold medicine, and allergy pills are not may be able to access on their own. However, if your doctor writes a prescription for any of these items, they become FSA-may be able to access. Bandages, first-aid supplies, and some other medical items are may be able to access without a prescription.

Can I use my FSA for my spouse or children?

Yes. FSA funds can be used for any family member you claim as a dependent on your taxes, including your spouse and children. The money does not have to be used only for the person whose name is on the account.

What if I submit a reimbursement request but do not have the original receipt?

Most plan administrators will not reimburse without a receipt. If you lost it, contact the provider or pharmacy and ask for a duplicate receipt or itemized statement. Keep these documents for at least three years in case of an IRS audit. If you cannot obtain proof, you may not be able to recover that expense from your FSA.