If you use your FSA incorrectly by charging something that isn’t a qualified medical expense, your plan administrator will deactivate your debit card and start a correction sequence set by IRS rules: repay the amount, substitute an eligible receipt, or have the charge added to your taxable wages at year-end. Most mistakes can be cleaned up before any tax hits your W-2, but only if you respond to the administrator’s notices quickly.
The Correction Steps Your Administrator Must Follow
When a debit card charge can’t be substantiated as a qualified medical expense, Proposed Treasury Regulation § 1.125-6(d)(7) tells your administrator to work through a specific sequence until the money is recovered.1Internal Revenue Service. IRS Memorandum 201413006 The steps escalate, and each one gives you another chance to fix it.
- Debit card deactivation. The card is shut off right away. You can’t use it for anything, including legitimate medical purchases, until the issue is closed. You can still tap your balance by submitting paper or digital claims with receipts.
- Repayment demand. The administrator sends a notice asking you to repay the exact dollar amount, usually by check or electronic transfer.
- Payroll withholding. If you don’t repay, your employer can withhold the amount from your paycheck or other compensation to the extent the law allows.
- Claims offset. Any remaining balance can be recovered by reducing future reimbursements. If you owe $200 and later submit a valid $250 claim, you receive $50.
- Business debt. If the money still hasn’t been recovered, the employer treats the amount as a debt owed to the company and uses its normal collection procedures.
Your card stays deactivated the entire time. Once the charge is resolved, the administrator restores it.
What It Costs You if the Charge Is Never Corrected
If a flagged charge never gets repaid or offset, the administrator reclassifies the amount as taxable wages and adds it to your Form W-2. You then owe federal income tax on it at whatever bracket applies to your total income; for 2026, those rates run from 10% to 37%.2Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 You also owe your share of FICA: 6.2% for Social Security and 1.45% for Medicare, a combined 7.65%.3Social Security Administration. Social Security and Medicare Tax Rates Your employer pays a matching 7.65% on its side.
The reason the money becomes taxable comes from 26 U.S.C. § 125. A cafeteria plan, which is the umbrella structure that includes your FSA, keeps your contributions out of gross income only when the plan funds qualifying benefits.4Office of the Law Revision Counsel. 26 USC 125 – Cafeteria Plans Spend on something that doesn’t qualify, and that shelter falls away.
One piece of good news: FSAs do not carry the extra 20% penalty tax that hits non-qualified HSA distributions. On a $500 ineligible charge, someone in the 22% bracket would owe roughly $148 in combined federal income tax and FICA. That’s a real cost, but nothing like the HSA penalty stack.
Three Ways to Fix a Flagged Charge
You generally have three routes to close out a flagged charge before it lands on your W-2: pay the money back, offset it with an eligible receipt you haven’t used yet, or prove the original charge was actually qualified.
Repay the Amount Directly
The cleanest fix is writing a check or making an electronic payment to your plan for the exact amount of the flagged charge. Once it clears, the administrator turns your card back on and the matter is closed. No tax follows because the plan has been made whole.
Substitute an Eligible Receipt
If you paid out of pocket for a qualifying medical expense during the same plan year and never submitted it, that receipt can offset the ineligible charge. IRS guidance lets administrators apply a substantiated claim against an earlier unsubstantiated one.1Internal Revenue Service. IRS Memorandum 201413006 The substitute receipt has to match or exceed the flagged amount and be for an expense incurred during the same coverage period. If it’s larger, you get the difference reimbursed as a normal claim.
Prove the Original Charge Was Eligible
Some charges are legitimate but weren’t documented well at the time. Gather better records and resubmit. For items that require a medical recommendation, such as vitamins or supplements taken to treat a specific condition, a letter of medical necessity from your doctor can turn a denial into an approval.5Internal Revenue Service. Publication 502, Medical and Dental Expenses
Documentation Your Administrator Will Accept
IRS rules require every FSA reimbursement to be backed by a written statement from an independent third party, such as a provider receipt, an insurance explanation of benefits, or a pharmacy printout.6Internal Revenue Service. Publication 969, Health Savings Accounts and Other Tax-Favored Health Plans The documentation should include:
- Date of service or purchase. The day the expense was incurred, not the day you paid.
- Provider or merchant name. The doctor’s office, pharmacy, lab, or other medical provider.
- A specific description. Something like “office visit,” “prescription — amoxicillin,” or “dental crown.” Generic labels like “medical supplies” are often rejected.
- Your out-of-pocket amount. The portion not covered by insurance.
Credit card statements alone don’t cut it. They show a merchant and an amount but not what was bought. Keep a running folder of medical receipts through the year so you can pull them fast if a charge is questioned.
Appealing a Denial
If you believe a denied claim was actually for an eligible expense, most plans have a formal appeal process. Timelines and steps vary, but a typical path involves asking the administrator for a detailed explanation of the denial, then submitting a written appeal with additional documentation. Some plans offer several rounds, including review by an independent third party.
Federal employees’ FSAs, for example, allow an initial informal inquiry within 30 days, a formal written appeal within 60 days of the original decision, and up to two additional review levels with 30-day filing windows each.7FSAFEDS. File an Appeal Private plans set their own deadlines, so pull your plan’s summary plan description. Missing the first deadline the administrator gives you can end your appeal rights.
Where the Mistakes Usually Come From
Your FSA can only reimburse expenses that meet the tax code’s definition of medical care under 26 U.S.C. § 213(d): amounts paid to diagnose, treat, cure, or prevent disease, or to affect a structure or function of the body.8Office of the Law Revision Counsel. 26 U.S. Code 213 – Medical, Dental, Etc., Expenses The definition covers a lot, including some items people don’t expect, like smoking-cessation programs, prescription sunglasses, and hearing aids. It stops at anything used to maintain general health rather than to treat or prevent a specific condition.
Charges that commonly trip the wire:
- Vitamins and supplements without a doctor’s recommendation tied to a diagnosed condition.5Internal Revenue Service. Publication 502, Medical and Dental Expenses
- Cosmetics and skin care, including moisturizers, anti-aging creams, and general-purpose sunscreen.
- Gym memberships and fitness classes, even when a doctor suggests exercise.
- Toiletries like toothpaste, deodorant, shampoo, baby wipes, and cotton swabs.
- Cosmetic procedures such as teeth whitening or breast enhancement.
- General-wellness foods, including low-calorie foods, protein powders, and nutritional shakes bought for general health.
Over-the-counter pain relievers, allergy pills, and cold medicine are generally eligible without a prescription. The problem often comes from mixed receipts at pharmacies and big-box stores, where a single transaction includes both eligible and ineligible items. Only the ineligible portion gets flagged, but the flag still triggers the whole correction process for that amount.
If You Leave Your Job With an Unresolved Charge
Quitting or being laid off does not erase a flagged FSA charge. The plan can still pursue collection through the steps above, and it can still add the amount to your final W-2 as taxable wages if nothing else works.
Once your employment ends, you generally lose access to the FSA balance. You can submit claims for eligible expenses incurred before your termination date, but you can’t use the account for new expenses unless you elect COBRA continuation coverage. Employers that sponsor health FSAs are typically required to offer COBRA to participants whose accounts are underspent, meaning the remaining balance exceeds what COBRA premiums would cost for the rest of the plan year. If the account is overspent, the employer may not be required to offer COBRA at all. Anything left in the account at plan-year end is forfeited if you don’t elect COBRA.
One boundary worth naming, because it looks like the same problem but isn’t: money left unspent at the end of the plan year isn’t a “misuse” of the FSA. It’s a separate forfeiture rule, and it doesn’t trigger the correction sequence or the tax treatment described here. It just disappears, subject to whatever grace period or carryover your employer has chosen to offer.