An FSA is worth it if you spend money on may be able to access medical or dependent care costs that you would pay anyway, and you can predict roughly how much you'll spend

An FSA saves you money by letting you set aside pre-tax dollars for healthcare and dependent care expenses. The math is straightforward: if you contribute $2,000 to an FSA and your tax rate is 22 percent, you avoid paying $440 in federal income tax on that money. That's an automatic return before you even use the account.

The trade-off is the use-it-or-lose-it rule. Money you don't spend by the end of the plan year (usually December 31) goes back to your employer — you cannot carry it forward or get it back. This means an FSA only makes sense if you're confident you'll spend what you contribute. If you guess wrong and contribute too much, you lose the difference.

Whether an FSA is worth it depends on three things: what you actually spend on may be able to access costs, how predictable that spending is, and whether you have other ways to cover those costs if you don't use all the money.

Key Takeaways

  • An FSA saves you money on taxes only if you spend the full amount you contribute before the plan year ends.
  • Common may be able to access expenses include copays, deductibles, prescription medications, dental work, vision care, and dependent care (daycare or after-school programs).
  • If you cannot predict your medical spending or you're unsure whether you'll use the money, an FSA carries the risk of forfeiting unused funds.
  • An FSA is most valuable if you have regular, predictable costs like monthly prescriptions, ongoing dental treatment, or consistent childcare expenses.

When the tax savings outweigh the risk

An FSA makes financial sense when you have costs you know you'll incur. If you take a daily prescription medication, wear contacts, or pay for regular therapy sessions, you already know roughly what you'll spend. If you pay for childcare while you work, that cost is usually stable month to month. In these situations, contributing to an FSA is a low-risk way to reduce your tax bill.

The larger your tax rate, the bigger your savings. Someone in the 24 percent federal tax bracket who contributes $2,500 to an FSA saves $600 in federal taxes alone — and may also save on state and payroll taxes depending on where they live. That's real money back in your pocket, even before you use a single dollar from the account.

An FSA also makes sense if you're planning a specific medical procedure you know is coming. If you're scheduled for dental work, vision correction, or a surgery during the plan year, you can estimate the out-of-pocket cost and contribute accordingly. Once you know the expense is covered by the FSA, you've locked in the tax savings.

When an FSA is risky

An FSA becomes a bad bet when your medical spending is unpredictable. If you rarely see a doctor, don't take regular medications, and have good health insurance with a low deductible, you might contribute $1,500 and spend only $300. You lose $1,200. That wipes out any tax savings and costs you money.

The same risk applies if you're changing jobs, moving to a new insurance plan, or experiencing a major life change during the year. If you contribute based on your current situation and then circumstances shift — you switch to a plan with different copays, you move to a state with different costs, or your health needs change — you may end up with unused money.

An FSA is also risky if you have a high deductible health plan (HDHP) and you're trying to decide between an FSA and a health savings account (HSA). An HSA lets you roll money forward year to year, so it's more forgiving if you don't spend everything. An FSA does not.

How to estimate whether you'll use the money

Start by looking at what you actually spent on may be able to access costs in the past year. Pull up your insurance statements, pharmacy receipts, and daycare invoices. Add up copays, deductibles you paid out of pocket, prescription costs, dental work, vision care, and dependent care. That number is your baseline.

Then ask yourself: will that spending stay the same, increase, or decrease this year? If you're starting a new medication, planning a dental procedure, or adding a second child to daycare, your costs will go up. If you're switching to a plan with lower copays or you expect fewer doctor visits, your costs may go down. Adjust your baseline accordingly.

Most people should contribute conservatively — somewhere between 80 and 100 percent of what they expect to spend. This gives you a buffer for unexpected costs while reducing the risk of forfeiting money. If you spent $2,000 last year and expect similar spending this year, contributing $1,800 or $2,000 is reasonable. Contributing $2,500 "just in case" is riskier.

The dependent care FSA angle

A dependent care FSA (also called a dependent care account) works the same way as a healthcare FSA but covers childcare, after-school programs, and adult day care. The contribution limit is lower — $5,000 per year for most people, or $2,500 if you're married and filing separately — but the tax savings are the same.

A dependent care FSA is often worth it because childcare costs are predictable. If you pay $1,200 a month for daycare, you know you'll spend $14,400 a year. Contributing that amount to an FSA saves you roughly $3,100 in taxes (at a 22 percent rate). That's a significant return, and the risk of forfeiting money is low because you know exactly what you'll spend.

The main exception is if your childcare costs are about to change — you're moving your child to school, switching providers, or reducing hours. In that case, estimate conservatively so you don't overcontribute.

Comparing an FSA to other options

If you have access to both an FSA and an HSA, the HSA is usually the better choice because you can roll money forward indefinitely. An HSA also has lower contribution limits but higher tax advantages. However, you can only open an HSA if you're enrolled in a high deductible health plan, and not everyone has that option.

If you don't have an HSA available, an FSA is worth it as long as you're confident you'll spend the money. If you're unsure, you're better off not contributing and paying for may be able to access costs with after-tax dollars. The tax savings aren't worth the risk of losing money you don't use.

Some people use a hybrid approach: they contribute a conservative amount to an FSA (enough to cover predictable costs like prescriptions and copays) and pay for unexpected medical expenses out of pocket. This reduces the risk of forfeiting money while still capturing tax savings on costs you know are coming.

What happens to unused FSA money

At the end of the plan year, any money left in your FSA goes back to your employer. You don't get it back as a refund, and you can't roll it forward to next year. Some employers offer a grace period (usually two months into the next year) where you can still spend money from the previous year's FSA, but this is optional and not all employers provide it. Check your plan documents to see if your employer offers a grace period.

A small number of employers allow you to carry forward up to $570 (in 2024) to the next plan year, but this is rare. Most FSAs operate under strict use-it-or-lose-it rules. This is why estimating correctly matters so much — overcontributing costs you real money.

Frequently Asked Questions

Can I change my FSA contribution during the year?

You can only change your contribution if you have a may have access to life event: marriage, divorce, birth or adoption of a child, loss of other health coverage, or a significant change in your dependent care costs. A change in your health or a new diagnosis does not count as a may have access to event. You must request the change within 30 days of the event.

What if I leave my job before I use all my FSA money?

When you leave your job, you typically lose access to any unused FSA money. Some employers allow you to continue using the FSA through the end of the plan year (called COBRA continuation), but you have to pay the full premium yourself. Check with your employer's benefits office about what happens to your account when you leave.

Is an FSA worth it if I have a high deductible health plan?

If you have an HDHP, you should prioritize an HSA over an FSA because HSA money rolls forward year to year. However, you can have both an FSA and an HSA at the same time — the FSA can cover dependent care or other may be able to access costs while the HSA covers medical expenses. Check your plan rules, as some employers restrict this combination.

How do I know if I'm overestimating my FSA contribution?

If you're unsure, look at your actual spending from the past two years and take the lower number. If you spent $1,500 one year and $2,000 the next, contribute $1,500 or $1,600. It's better to leave some money on the table than to forfeit a large amount. You can always pay for unexpected costs out of pocket.

Does an FSA reduce my taxable income for state taxes too?

Most states treat FSA contributions the same way the federal government does — as pre-tax deductions that reduce your state taxable income. However, a few states (including New Jersey, Pennsylvania, and Illinois) do not allow this deduction for state tax purposes. Check your state's tax rules or ask your employer's benefits office.