How to Open an FSA Account: Types, Contributions, and Enrollment

To open an FSA account, you enroll through your employer’s cafeteria plan during open enrollment, within your new hire window, or after a qualifying life event; there is no bank, brokerage, or individual marketplace where you can set one up on your own. You choose the type of Flexible Spending Account offered, elect an annual contribution amount within IRS limits, and your employer begins deducting that amount from your paychecks before taxes.

Confirm You’re Eligible to Enroll

FSAs exist only inside employer-sponsored cafeteria plans authorized by Section 125 of the Internal Revenue Code. If your employer doesn’t offer a cafeteria plan, you can’t open one independently. The statute defines a cafeteria plan as a written plan where all participants are employees who choose among cash and qualified benefits.¹

The “all participants are employees” language matters. Self-employed people don’t qualify because they aren’t employees of anyone.² Partners in a partnership are treated as self-employed for tax purposes and are similarly excluded. Shareholders who own more than 2% of an S-corporation are also barred; the IRS specifically states they may not participate in a flexible spending arrangement.³ If you fall into any of these categories and have employees of your own, you can sponsor a cafeteria plan for your staff, but you can’t enroll in it yourself.

Know When You Can Enroll

Federal rules limit FSA enrollment to specific windows. Miss your window and you generally wait until the next one.

Open Enrollment

Most employers run an annual open enrollment period, typically in the fall, for benefits taking effect January 1 or the start of the plan year. This is the main opportunity to enroll in an FSA for the first time, change your contribution amount, or drop coverage. FSA elections don’t automatically roll over. If you skip open enrollment without acting, you generally go the entire next plan year without an FSA.

New Hire Enrollment

New employees typically get 30 days from their start date to elect FSA benefits. Some employers extend this to 60 days, but 30 is the most common window. Miss it and you’ll wait until the next open enrollment unless a qualifying life event occurs.

Qualifying Life Events

Outside those windows, you can enroll or change an election only after a qualifying life event, such as:

Marriage or divorce that affects your tax filing or insurance coverage
Birth or adoption of a child
A spouse’s job change that adds or ends coverage through their employer
A change in employment status, such as moving between full-time and part-time in a way that affects benefit eligibility

You generally have 30 days from the event to request the change, and the new election must be consistent with the event. A new baby, for example, doesn’t justify tripling your health care FSA contribution if the increase isn’t tied to that dependent’s expenses.

Pick the Right Type of FSA

Your enrollment form will ask you which FSA you want. Employers may offer one type or several, and choosing the wrong one can leave your funds unusable for the expenses you had in mind.

Health Care FSA

A general-purpose health care FSA covers medical, prescription, dental, and vision expenses, including copays, deductibles, prescription drugs, eyeglasses, and dental work. For 2026, the maximum contribution is $3,400.⁴ One feature to plan around: the full annual election is available on the first day of the plan year. If you elect $3,400 and have a $2,000 dental bill in January, the FSA will reimburse the full amount even though your payroll deductions have barely started.

Limited Purpose FSA

A limited purpose FSA reimburses dental and vision expenses only. It exists for a specific reason: it’s the only type of health FSA you can hold alongside a Health Savings Account. A general-purpose health care FSA disqualifies you from contributing to an HSA; a limited purpose FSA does not.⁵ If you have a high-deductible health plan and want to fund an HSA, this option preserves pre-tax help for dental and vision costs without breaking HSA eligibility. The 2026 limit is the same $3,400.⁴

Dependent Care FSA

A dependent care FSA covers childcare, preschool, summer day camp, before- and after-school programs, and adult daycare for a qualifying dependent.⁶ It cannot be used for a child’s doctor visits or prescriptions. The maximum exclusion for 2026 is $7,500 per household, or $3,750 if you’re married and filing separately.⁷ Unlike a health care FSA, the full annual amount is not available on day one. Reimbursement is capped at what you’ve actually contributed through payroll deductions so far.

Decide How Much to Contribute

This is the step where people either leave money on the table or lose it. FSAs generally operate under a use-it-or-lose-it rule, so money left in the account at year-end is forfeited.

For a health care FSA, start by reviewing last year’s medical bills: copays, prescriptions, dental cleanings, glasses, and any planned procedures. If you’re expecting a predictable cost like braces or a surgery, factor it in. For a dependent care FSA, add up your childcare costs for the year. The 2026 ceilings are $3,400 for a health care FSA and $7,500 per household for a dependent care FSA.⁴⁷

When in doubt, go conservative. Losing $500 to forfeiture hurts more than missing $500 in potential tax savings, because forfeited money is gone entirely while the missed savings would only have been a fraction of that amount.

Check Your Plan’s Carryover or Grace Period First

The use-it-or-lose-it rule has two possible safety valves, and your employer decides whether to offer either. They can’t offer both.

Carryover: your plan may allow you to roll over unused health care FSA funds into the next plan year, up to $680 for plan years beginning in 2026. Anything above that is still forfeited. You must re-enroll in the FSA the following year to access the carryover.⁴
Grace period: some plans give you an extra two months and 15 days after the plan year ends to spend remaining funds on eligible expenses. For a calendar-year plan, that runs until March 15.⁸

Some employers offer neither, meaning unspent funds vanish at year-end. Check your plan documents before you finalize your election. This one detail should shape how aggressively you contribute.

Complete the Enrollment Form

Most employers use a digital benefits portal, either their own HR system or a third-party administrator’s website. You’ll typically need:

Account type selection: health care FSA, limited purpose FSA, or dependent care FSA, or a combination if your employer offers more than one
Annual election amount, which gets divided equally across your paychecks
Personal information: Social Security number, date of birth, and contact details
Dependent information for a dependent care FSA: names and dates of birth of qualifying dependents

Some employers still route paper forms through a benefits coordinator. Either way, double-check your account type and elected amount before submitting. A typo can mean contributing too much and risking forfeiture, or too little and paying for eligible expenses with taxed dollars. After submission, you should receive a confirmation email or benefits summary statement. Save it. If a dispute arises about your election or start date, that document is your proof.

What Happens After You Enroll

Once your plan year begins and payroll deductions start, most administrators issue a debit card linked to the account. You can use it at pharmacies, doctor’s offices, and other qualifying providers to pay for eligible expenses directly. Many administrators also offer a mobile app for submitting claims and uploading receipts.

The IRS requires that every FSA expense be substantiated, meaning you may need to provide documentation proving the expense was eligible. Some debit card transactions are verified automatically, such as a copay that matches an amount on file with your insurance plan. Many require you to submit a receipt or an explanation of benefits showing the date of service, the type of service, and the amount you owe.⁹ Simply telling your administrator “I had a medical expense” doesn’t count; the IRS explicitly prohibits self-certification. If you don’t respond to a substantiation request, the administrator can suspend your card or require you to repay the amount.

Keep every medical receipt and explanation of benefits statement throughout the year. The most common FSA headache isn’t forfeiture. It’s a denied claim because a receipt got thrown away and you can’t prove the expense was eligible.

1
Office of the Law Revision Counsel. 26 USC 125 – Cafeteria Plans
2
Social Security Administration. POMS SI 01120.230 – Health Flexible Spending Arrangements (FSAs)
3
Internal Revenue Service. S Corporation Compensation and Medical Insurance Issues
4
FSAFEDS. New 2026 Maximum Limit Updates
5
Internal Revenue Service. Individuals Who Qualify for an HSA
6
FSAFEDS. Dependent Care FSA
7
Office of the Law Revision Counsel. 26 USC 129 – Dependent Care Assistance Programs
8
Internal Revenue Service. Modification of Use-or-Lose Rule For Health Flexible Spending Arrangements (FSAs)
9
Internal Revenue Service. Notice 2006-69 – Debit Cards Used to Reimburse Participants