HSA and FSA Denied Expense Claims: How to Appeal

Health Savings Accounts (HSAs) and Flexible Spending Accounts (FSAs) are supposed to make paying for medical expenses easier. But when a reimbursement claim is denied — or a debit card transaction is flagged — it can feel like you're being penalized for spending your own money. Understanding the rules that govern these accounts and how to challenge a wrongful denial is essential.

How HSAs and FSAs Work

HSA (Health Savings Account): Available only to people enrolled in a High-Deductible Health Plan (HDHP), an HSA allows pre-tax contributions that can be used tax-free for qualified medical expenses. Funds roll over year to year and the account is owned by the individual. HSAs are governed by IRS rules, primarily Section 223 of the Internal Revenue Code.

FSA (Flexible Spending Account): Available through employer-sponsored plans, an FSA allows pre-tax contributions that can be used for qualified expenses within the plan year (with optional grace period or carryover provisions). Unlike HSAs, FSAs are employer-owned accounts governed by Section 125 of the Internal Revenue Code and ERISA.

Both accounts define eligible expenses by reference to IRS Publication 502, which lists "medical expenses" deductible under Section 213(d) of the Internal Revenue Code.

What Counts as a Qualified Medical Expense

IRS Publication 502 is the definitive guide to qualified medical expenses. Common covered categories include:

• Doctor, hospital, and lab fees
• Prescription drugs and insulin
• Dental and vision care
• Mental health treatment (therapy, psychiatry)
• Medical equipment and supplies
• Certain over-the-counter (OTC) items expanded by the CARES Act (2020) — including OTC drugs and menstrual care products without a prescription

Common expenses that are NOT qualified:

• Cosmetic surgery (unless medically necessary)
• General health items like vitamins, unless prescribed
• Gym memberships (unless prescribed for a specific medical condition — and even then, documentation matters)
• Teeth whitening
• Funeral expenses

If your FSA or HSA reimbursement was denied for an expense you believe is qualified, the first step is to verify it against the current version of IRS Publication 502.

Substantiation Requirements: The Root of Many Denials

The IRS requires that FSA expenses be substantiated before reimbursement. This means the plan must verify that:

1. The expense was for a qualified medical expense (not a general consumer purchase)
2. The expense was not previously reimbursed
3. The amount is supported by documentation

For debit card transactions: Many FSA debit cards can be used at merchants with a specific Merchant Category Code (MCC) or an Inventory Information Approval System (IIAS) that verifies the item is a qualified medical product at point of sale. If you use your FSA card at a pharmacy, the card may auto-approve qualified items. But if you use it at a general retailer or buy a mixed cart, the transaction may require additional substantiation.

Substantiation failure consequences: If the plan administrator determines a transaction hasn't been substantiated, they may:

• Deny the reimbursement
• Request that you repay the amount to the FSA
• Suspend your debit card until you resolve the outstanding balance

Debit Card Dispute vs. Reimbursement Dispute

Debit card dispute: You used your FSA debit card and the plan is now asking for substantiation or repayment. To resolve this, submit receipts showing the date, provider or merchant, amount, and nature of the purchase. If you paid for a qualified service, your EOB)" class="auto-link">Explanation of Benefits (EOB) from your health insurer typically suffices.

Reimbursement denial: You submitted a claim for reimbursement and the plan denied it. This is more common with HSAs processed by custodian banks or when FSA administrators apply overly restrictive interpretations of eligible expenses.

How to Appeal an FSA Denial

FSAs are employer-sponsored plans typically subject to ERISA. This means you have the full ERISA claims and appeals framework:

1. Request the denial in writing with specific reasons if you haven't received one
2. Review your plan's FSA Summary Plan Description to see exactly how your plan defines eligible expenses
3. Submit your appeal with IRS Publication 502 citations showing the expense is qualified, along with medical records if needed (e.g., a physician's statement that the item is medically necessary)
4. Escalate to ERISA review if the plan's internal appeal fails

For procedures like LASIK, orthodontia, or mental health treatment that are sometimes disputed, a letter from your physician explaining the medical necessity can be decisive.

How to Appeal an HSA Denial

HSA disputes are somewhat different because the account is owned by the individual and administered by a custodian (typically a bank or financial institution). If the custodian incorrectly denies a distribution or reports a distribution as non-qualified:

1. Document that the expense is qualified under IRS Publication 502
2. Contact the custodian's appeals department in writing
3. Consult a tax professional if the dispute involves a tax reporting question (e.g., whether a 1099-SA was issued correctly)
4. If the custodian refuses to correct an error, you can raise the issue with the IRS in connection with your tax return, or file a complaint with bank regulators

Fight Back With ClaimBack

HSA and FSA denials often come down to documentation and definitions. ClaimBack helps you understand what qualifies, gather the right evidence, and craft an appeal that presents your case clearly.

Start your appeal at ClaimBack

Related Reading:

• How to Write an Insurance Appeal Letter
• What Is Medical Necessity?
• Common Reasons Insurance Claims Are Denied