The amount you contribute to your FSA depends on your household expenses, tax bracket, and how much you can afford to set aside without creating a cash flow problem

There is no minimum or maximum that works for everyone. The IRS sets an annual limit — currently $3,300 for individual coverage — but that does not mean you should contribute the full amount. The real question is: how much will you actually spend on may be able to access medical expenses in the next 12 months, and how much can you afford to lock away in an account you cannot touch without penalty?

Most people underestimate their medical spending. Copays, deductibles, prescription refills, dental work, and vision care add up faster than expected. The trade-off is that money you do not spend by the end of the plan year is forfeited — with rare exceptions — so overestimating costs you real money.

Key Takeaways

  • The IRS limit for 2024 is $3,300 per year for individual coverage, but you choose how much of that to contribute based on your own spending patterns.
  • Money in an FSA reduces your taxable income, so a $2,000 contribution saves roughly $400 to $600 in federal and state taxes depending on your tax bracket.
  • Unused money at the end of the plan year is forfeited unless your employer offers a grace period (up to 2.5 months) or a carryover option (up to $640 in 2024).
  • Start by tracking what you actually spent on medical, dental, and vision care in the past year, then adjust for known changes like a new prescription or planned procedure.
  • If you are unsure, contribute less rather than more — the tax savings on a smaller amount are real, but forfeited money is gone entirely.

How the tax savings work

Money you put into an FSA comes out of your paycheck before federal income tax, Social Security tax, and Medicare tax are calculated. That means a $2,000 FSA contribution reduces your taxable income by $2,000.

If you are in the 22% federal tax bracket and your state has a 5% income tax, that $2,000 contribution saves you roughly $540 in taxes ($2,000 × 0.27). You get that money back immediately through smaller paychecks, not as a refund at tax time. The catch is that you only see the savings if you actually spend the money on may be able to access expenses — if you do not, you lose both the contribution and the tax benefit.

Calculating your actual medical spending

The most reliable way to choose a contribution amount is to look at what you spent in the past 12 months. Pull up your insurance statements, credit card bills, and receipts for the last year. Add up every copay, coinsurance amount, deductible payment, prescription cost, dental work, glasses, contacts, and hearing aids.

Do not guess. Write down the number. Most people are surprised — some find they spent far less than they thought, others discover they spent far more. Once you have the real number, adjust it for changes you know are coming: a new medication, a planned dental procedure, a change in your insurance plan, or a child aging out of your coverage.

If you spent $1,800 last year and nothing major is changing, contributing $1,800 to $2,000 is reasonable. If you spent $800 and your health is stable, do not contribute $3,300 just because the limit exists.

The forfeiture rule and how to avoid it

The use-it-or-lose-it rule is the biggest risk with FSAs. Money you do not spend by the end of your plan year (usually December 31) is forfeited. There are two exceptions, but they do not apply to everyone.

Some employers offer a grace period of up to 2.5 months after the plan year ends. If your employer has one, you can spend FSA money through mid-March on expenses you incurred during the grace period. Check your plan documents or ask your HR department whether yours offers this.

A smaller number of employers allow a carryover, meaning you can roll up to $640 (in 2024) of unused money into the next year. Again, this is optional for employers, so you have to ask whether your plan allows it. If it does, you can contribute more aggressively knowing that a small overage will not disappear.

If your plan has neither grace period nor carryover, be conservative. It is better to contribute $1,500 and use it all than to contribute $2,500 and forfeit $500.

Accounting for life changes during the year

You can change your FSA contribution only during open enrollment or 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 spouse's benefits. A job change or salary increase does not may have access to.

This means you should think carefully before locking in your contribution amount. If you are planning a major dental procedure in the fall, contribute enough to cover it. If you are starting a new medication in January, factor in the full-year cost. If you are unsure whether you will still be on your employer's plan in six months, contribute less.

What counts as an may be able to access expense

FSA money can pay for copays, coinsurance, deductibles, prescription drugs, dental work, vision care, hearing aids, and certain medical equipment. It cannot pay for health insurance premiums, over-the-counter medications (with rare exceptions), cosmetic procedures, or gym memberships.

Keep receipts for everything you buy with your FSA card or reimburse yourself for. Your plan administrator may ask for proof that an expense was may be able to access, and without documentation you may have to repay the money out of pocket.

Frequently Asked Questions

What happens if I contribute too much and do not spend it all?

The unused money is forfeited at the end of the plan year, unless your employer offers a grace period or carryover option. Check your plan documents to see which applies to you. If neither does, you lose the money — but you still got the tax savings on what you did spend.

Can I change my FSA contribution mid-year?

Only if you have a may have access to life event such as marriage, birth, adoption, divorce, or loss of other health coverage. A change in income or a new medical diagnosis does not may have access to. Plan your contribution carefully because you are locked in until the next open enrollment.

Should I contribute the maximum if I can afford it?

Not necessarily. Contribute the maximum only if you are confident you will spend it all. The tax savings are real, but forfeited money is a bigger loss than the tax benefit. If you are unsure, contribute what you actually expect to spend, then increase it next year if you come in under budget.

Does my spouse's FSA affect mine?

No. If you are both employed and both have access to an FSA, you each have a separate account with a separate $3,300 limit. You cannot combine contributions or share money between accounts. Coordinate your contributions so you do not duplicate coverage for family expenses.

What if my plan has a carryover option?

A carryover lets you roll up to $640 of unused money into the next year. This gives you more flexibility to contribute slightly more without risking total loss. If your plan offers it, you can be a bit more generous with your contribution amount.