Choosing between a health care FSA and a limited purpose FSA comes down to one question: are you contributing to a Health Savings Account? If yes, the limited purpose FSA is your only compatible option, because it restricts reimbursements to dental and vision expenses and preserves your HSA eligibility. If no, take the health care FSA, which reimburses almost any medical, dental, or vision cost and has no reason to be narrowed. Both accounts share the same $3,400 contribution limit for 2026.1Internal Revenue Service. Rev. Proc. 2025-19
What Each Account Actually Covers
A health care FSA reimburses qualified medical expenses under Section 213(d) of the tax code, which is a deliberately wide category.2Office of the Law Revision Counsel. 26 U.S. Code 213 – Medical, Dental, Etc., Expenses Doctor visit copays, prescriptions, lab work, imaging, physical therapy, mental health counseling, and medical equipment all qualify. So do dental cleanings, fillings, crowns, eye exams, glasses, contacts, and LASIK.3Internal Revenue Service. Frequently Asked Questions About Medical Expenses Related to Nutrition, Wellness and General Health Over-the-counter medications and menstrual care products have been permanently eligible without a prescription since the CARES Act.4Internal Revenue Service. IRS Outlines Changes to Health Care Spending Available Under CARES Act
A limited purpose FSA covers dental and vision only. Cleanings, fillings, crowns, orthodontics, periodontal work, eye exams, prescription glasses, contact lenses, lens solution, and corrective procedures like LASIK all qualify. Nothing else does. That narrow scope is the point.
Why the Limited Purpose Version Exists
To contribute to a Health Savings Account, you must be enrolled in a High Deductible Health Plan and carry no other disqualifying health coverage. A general health care FSA counts as disqualifying coverage because it reimburses medical expenses before you’ve met your HDHP deductible. Enroll in both simultaneously and the IRS treats you as ineligible for the HSA, which means income tax on your HSA contributions plus a 6% excise tax on the excess for every year it sits in the account.5Internal Revenue Service. Publication 969 – Health Savings Accounts and Other Tax-Favored Health Plans
The limited purpose FSA solves that problem. Because it reimburses only dental and vision costs, the IRS classifies it as permitted coverage that doesn’t interfere with HSA eligibility.6U.S. Department of the Treasury. Revenue Ruling 2004-45 – Section 223 Publication 969 confirms that an employee can contribute to an HSA while also participating in a limited-purpose health FSA.5Internal Revenue Service. Publication 969 – Health Savings Accounts and Other Tax-Favored Health Plans
The reason to bother is the combined savings ceiling. In 2026, HSA contribution limits are $4,400 for self-only HDHP coverage and $8,750 for family coverage, and those stack on top of the $3,400 limited purpose FSA.1Internal Revenue Service. Rev. Proc. 2025-19 That’s up to $7,800 in combined pre-tax health savings for a single individual, or $12,150 for a family. An additional $1,000 HSA catch-up contribution is available if you’re 55 or older. HSA funds roll over indefinitely and can be invested; the limited purpose FSA handles predictable dental and vision costs on a use-it-or-lose-it basis.
When the Health Care FSA Is the Right Choice
If you’re not enrolled in an HDHP and don’t plan to open an HSA, take the health care FSA. It covers everything the limited purpose FSA covers plus medical care, prescriptions, mental health services, and the rest of Section 213(d). In this scenario, the limited purpose FSA is a worse version of the same account. There is no upside to accepting narrower coverage when you gain nothing in exchange.
The tax benefit is the same regardless of which version you pick. FSA contributions made through payroll deduction are exempt from federal income tax and from Social Security and Medicare taxes.7FSAFEDS. FAQs Someone in the 22% federal income tax bracket saves roughly $220 in income tax plus $76.50 in FICA on every $1,000 contributed, close to 30% combined. Actual savings depend on your marginal rate, and a handful of states, including New Jersey, don’t follow the federal pre-tax treatment for cafeteria plan benefits.
Your full annual election is available from the first day of the plan year even if only one paycheck has been deducted.8Internal Revenue Service. Modification of Use-or-Lose Rule for Health Flexible Spending Arrangements Elect $3,400 and need $2,000 of dental work in January, you can spend it immediately and let payroll catch up.
When the Limited Purpose FSA Is the Right Choice
Open the limited purpose FSA if you have an HSA-eligible HDHP, you’re contributing to the HSA, and you have predictable dental and vision expenses you’d otherwise pay from HSA funds. Glasses, contacts, cleanings, orthodontic installments, and planned LASIK are the classic candidates. Every dollar run through the limited purpose FSA instead of the HSA is a dollar that stays invested and grows tax-free for future use, potentially decades away.
If you have an HDHP but rarely see the dentist or eye doctor, the limited purpose FSA may not be worth the paperwork and forfeiture risk. You can pay those occasional costs from the HSA directly. The account earns its keep when dental and vision spending is high enough and predictable enough to justify committing pre-tax dollars you can’t recover if unused.
Orthodontic treatment is worth calling out here. Braces and aligners often span multiple plan years, and FSA funds generally must be used within the year. Match your annual election to the portion of treatment you’ll actually pay that year, not the total quoted cost. Installments falling in the next plan year come from the next year’s election or another source.
The Use-It-or-Lose-It Trap Applies to Both
Whichever account you choose, unspent funds at the end of the plan year are generally forfeited.5Internal Revenue Service. Publication 969 – Health Savings Accounts and Other Tax-Favored Health Plans Employers can soften that with one of two options, but not both:
- A carryover of up to $680 of unused funds into the next plan year for 2026. The carryover doesn’t count against your new election.
- A grace period of an extra 2½ months after the plan year ends to spend the balance on new expenses. For a calendar-year plan, that runs through March 15.
Some plans offer neither, in which case every unspent dollar disappears on December 31. Estimate conservatively. Leaving a small amount of tax savings on the table beats forfeiting hundreds of dollars.
For limited purpose FSA users, a carryover of limited purpose FSA funds into the next plan year generally keeps its limited-purpose character and won’t disqualify the HSA. The interaction depends on how your specific plan is structured, so confirm with your administrator before you assume.
What Happens When You Leave Your Job
Unused FSA funds generally don’t follow you when you separate from your employer. Your right to submit claims typically ends on your termination date, and any remaining balance reverts to the employer. This applies to both account types.
One exception: if your FSA is underspent when you leave, meaning you’ve contributed more through payroll than you’ve been reimbursed, you may be able to continue the account through COBRA for the rest of the plan year. You’d fund it yourself without payroll pre-tax treatment, and you can’t use FSA funds to pay the COBRA premiums. The math rarely works unless you have significant dental or vision spending already planned.
Your HSA belongs to you regardless of employment. The balance stays in your account and you can keep spending it on qualified medical expenses without a job. That portability is another argument for pairing the limited purpose FSA with an HSA when you’re eligible: the HSA builds a permanent asset while the FSA handles short-term, predictable costs you’d have spent anyway.
If You Run Both, Keep the Reimbursements Clean
The IRS prohibits double dipping, which means claiming the same expense from two different tax-advantaged accounts. When you take an HSA distribution, you must certify the expense hasn’t been reimbursed elsewhere. FSA claims carry the same attestation.5Internal Revenue Service. Publication 969 – Health Savings Accounts and Other Tax-Favored Health Plans Violations can jeopardize the tax-exempt status of both accounts.
The practical rule: dental and vision expenses go through the limited purpose FSA first; everything else goes through the HSA. If a dental bill exceeds your remaining FSA balance, pay the overage from the HSA, but don’t submit the same receipt to both.
The most common operational mistake is swiping the wrong card. Paying a dental bill with your HSA debit card instead of your FSA card isn’t illegal, but it burns HSA dollars that could have stayed invested. Some administrators let you reverse and reprocess an accidental charge; some don’t. Reserve the FSA card for dental and vision providers and use the HSA card everywhere else.
Ask About a Post-Deductible Hybrid
Some employers offer a combination FSA that starts the year as limited purpose, then converts to a general-purpose FSA for the rest of the year once you’ve met your HDHP’s minimum annual deductible ($1,700 for self-only or $3,400 for family coverage in 2026).1Internal Revenue Service. Rev. Proc. 2025-19 To trigger the conversion, you typically submit an Explanation of Benefits showing the date your cumulative out-of-pocket spending hit that threshold. Only expenses incurred after that date qualify for general-purpose reimbursement.
Not every employer offers this design. If yours does and you’re on an HDHP, it preserves HSA eligibility early in the year while opening broader coverage later. Check your benefits materials before enrollment.