HSA vs FSA: Which One Fits You?

HSAs and FSAs both let you pay for medical costs with money that isn't taxed. They sound alike, but they work very differently. This guide puts them side by side so you can pick what fits your life.

The short version

• An HSA is like a medical savings account you own. It goes with you, and unused money stays yours year after year. But you can only contribute if you have a qualifying high deductible health plan.
• An FSA is a yearly spending account through your employer. You get your full yearly amount up front, but leftover money is generally lost at year end (with some exceptions).

Side-by-side comparison

Sources for the table: IRS Publication 969, IRS Revenue Procedures 2026-24 and 2025-32. Max carryover from a 2026 FSA plan year: $680.

Can I have both?

Usually not a regular one of each. IRS Publication 969 says someone with an HDHP who is also covered by a health FSA that pays general medical expenses generally can't contribute to an HSA. This includes coverage through a spouse's general-purpose FSA.

But there are exceptions the IRS allows alongside an HSA, including:

• A limited-purpose FSA, which pays for things like dental and vision care (and preventive care).
• A post-deductible FSA, which doesn't pay medical costs until you meet a minimum deductible.

If your employer offers a limited-purpose FSA, you could use it for dental and vision costs and save your HSA for later.

Which one fits you? Some questions to ask

Did you pick an HDHP (or another HSA-eligible plan)? If no, the HSA is off the table. An FSA may still help.

Do you want to save for the future? An HSA lets money roll over and grow. Some people use it as a long-term savings account for health costs.

Do you have a big expense early in the year? An FSA gives you your full yearly amount right away. That can help if you know you'll have surgery or dental work in the spring.

Are you worried about losing money? With an HSA, unused money is yours. With an FSA, choose a careful amount based on costs you expect.

Are you close to Medicare? Once you're enrolled in Medicare, the IRS says you can't contribute to an HSA anymore (but you can still spend what's there).

Two made-up examples

Made-up example 1: Kim is 30, healthy, and picks an HDHP. She opens an HSA and puts in what she can. She rarely spends it, so it builds up for future medical costs. She also signs up for a limited-purpose FSA to cover her yearly glasses and dental cleanings.

Made-up example 2: Carlos picks a PPO because his kids see specialists often. He can't contribute to an HSA with that plan. He signs up for a health FSA and elects an amount equal to the copays and prescriptions he paid last year, so he's unlikely to lose money.

Don't mix these up

• HRA (health reimbursement arrangement): IRS Publication 969 says an HRA is funded only by your employer. You can't put your own money in.
• Dependent care FSA: This is for child or dependent care, not medical bills. It has its own separate limit ($7,500 for 2026, per IRS Publication 15-B).