FSA Use-It-or-Lose-It Rule Explained

The FSA use-it-or-lose-it rule requires employees to spend their elected Flexible Spending Account balance by year-end or forfeit the unused portion to their employer—a feature that makes FSA planning time-sensitive and occasionally costly. Two employer-permitted exceptions—the $640 carryover (in 2024) and the grace period—can ease this constraint, but both require advance employer election and careful deadline tracking.

Why the forfeiture rule exists

The FSA is funded with pre-tax dollars—a tax benefit that’s worth roughly 20–40% of the contribution, depending on the employee’s tax bracket. To prevent the account from becoming a permanent tax shelter, the IRS imposed the use-it-or-lose-it rule. If balances could roll indefinitely, employees could stash unlimited pre-tax savings and claim them years later, eroding tax revenue.

The rule is a trade-off: employees get a tax discount on out-of-pocket medical and childcare costs, but must plan carefully to avoid waste.

How the carryover exception works

Starting in 2013, the IRS permitted employers to allow up to $570 of unused FSA funds to roll to the next plan year (the limit increases annually for inflation; in 2024 it rose to $640). The carryover:

• Applies only if the employer amends the plan to permit it
• Is optional for employees—unclaimed money after the rollover still forfeits
• Does not stack with the grace period (an employer picks one or the other)
• Comes with a separate deadline (usually Dec. 31 of the rollover year)

An employee with a $2,500 health FSA who uses $1,900 in Year 1 has $600 unused. If the employer permits carryover, $570 rolls to Year 2, and $30 forfeits. That $570 can be claimed in Year 2 for eligible expenses.

The grace period alternative

If the employer elects a grace period instead of carryover, employees get an extended deadline: usually March 15 of the following year (though the IRS allows up to 2.5 months after plan year-end, so some employers use March 31 or April 15).

The grace period applies to expenses incurred during the prior plan year. An employee with $400 left on Dec. 31, Year 1, can submit claims for Year 1 medical expenses through the grace-period deadline (e.g., March 15, Year 2). If that claim is for $450, it covers the $400 balance plus an overage draw (which is not permitted).

The grace period is often more valuable for dependent-care FSA, because childcare expenses tend to be predictable and easily documented months after they occur.

Practical spend-down tactics

Track claims in real time: Many FSA administrators offer online portals showing the current balance and submitted claims. Review monthly to gauge pace.

Front-load predictable expenses: If you know you’ll need glasses, refill prescriptions, or pay dental copays, submit receipts early in the year. Some expenses can be claimed retroactively.

Time elective procedures: Scheduling a non-emergency medical procedure (dental work, vision correction, dermatology) before year-end locks in a claim.

Dependent-care: use it gradually: If you have dependent-care FSA, childcare is a steady monthly expense. Track whether the elected amount aligns with actual usage by October; adjust if your plan permits mid-year changes.

Over-the-counter (OTC) items: As of 2020, OTC medications (cold medicine, antihistamines, pain relievers) and feminine hygiene products are FSA-eligible again. Stock up before the deadline if needed.

Pay out-of-pocket now, claim later: You can pay for eligible expenses out-of-pocket and submit the receipt months later, as long as it’s before the deadline. This flexibility lets you “top up” balances in December.

The overage problem

Overcontributing to an FSA is risky. If you elect $2,500 but only incur $2,100 in eligible expenses, you lose $400. The employer cannot refund forfeited amounts.

Unlike HSAs, which roll over indefinitely and earn interest, FSAs are use-it-or-lose-it by design. Employees should elect a conservative annual amount based on the prior year’s spending, accounting for life changes (new child, planned procedures, new insurance plan).

Eligible expenses: what counts

Health FSA covers:

• Copays, coinsurance, deductibles (after insurance)
• Prescriptions and OTC medications (with doctor’s note pre-2020)
• Vision: glasses, contacts, exams, laser surgery
• Dental: cleanings, fillings, braces, root canals
• Mental health services
• Physical therapy
• Hearing aids and batteries

Dependent-care FSA covers:

• Licensed daycare (center or home-based)
• Summer camp (if the camp enables the parent to work)
• Adult day care for a disabled spouse or parent
• Does not cover K–12 school tuition (unless after-school care)

Ineligible: cosmetic surgery, gym memberships, over-the-counter vitamins (unless prescribed), life insurance premiums.

Claiming after the deadline

Once the deadline passes—whether Dec. 31 (standard rule) or the grace-period date—no claims can be submitted for the forfeited balance, regardless of when the expenses occurred. If an employee incurred a $300 medical expense in November but didn’t submit the receipt until January, and the FSA has forfeited the balance, that $300 is lost.

This is why deadlines matter: the claim must be submitted by the deadline, not the expense incurred by the deadline.

Planning across life transitions

Changing jobs: FSA funds are not portable. If you leave an employer mid-year, you keep the FSA through COBRA (paying both employee and employer premiums), or you lose the remaining balance. Plan accordingly during job changes.

Marriage or divorce: These trigger qualifying life events in most plans, allowing a mid-year election change or new-spouse enrollment.

Birth or adoption: Similarly permits an FSA election change mid-year.

If these events occur late in the year, be cautious about increasing your FSA election; you’ll have less time to spend it down.

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