Open enrollment season is here, and millions of Americans are staring at the same two acronyms on their benefits portal: FSA and HSA.
Pick wrong and you could leave hundreds of dollars on the table, or worse, lose money you never get back.
Both accounts let you pay for medical costs with pre-tax dollars, but they follow completely different rulebooks.
The FSA, or flexible spending account, is the classic use-it-or-lose-it arrangement.
The HSA, or health savings account, works more like a retirement account for your body.
The biggest catch with an FSA is the deadline.
In most cases, you have to spend the money by the end of the plan year, though your employer may offer a grace period or let you roll over a small amount.
In 2025, workers can stash up to $3,300 in a health care FSA, or $6,600 for family coverage.
Any cash still sitting there when the clock runs out typically goes back to your employer.
The money never expires, it rolls over year after year, and you can invest the balance once it crosses a certain threshold.
For 2025, you can contribute up to $4,300 as an individual or $8,550 for family coverage.
People 55 and older can add another $1,000.
Here's the fine print that trips people up: you can only open an HSA if you're enrolled in a high-deductible health plan.
Not every employer offers one, and those plans often mean paying more out of pocket before coverage kicks in.
If your company offers a traditional PPO, the FSA may be your only option.
HSA contributions go in tax-free, grow tax-free, and come out tax-free for qualified medical expenses.
After age 65, you can withdraw the money for anything, though non-medical withdrawals get taxed like regular income.
That flexibility has pushed some financial planners to call the HSA the most tax-efficient account available to everyday workers.
FSAs do have one underrated perk: the full amount is available on day one.
If you elect $2,000, you can spend all of it in January even though the money comes out of your paycheck over twelve months.
HSAs only let you spend what's actually in the account.
There's also a dependent care version of the FSA, worth up to $5,000 per household, which covers daycare and summer camp costs.
If you're healthy, have a high-deductible plan, and can afford to pay small bills out of pocket, the HSA is usually the stronger long-term play.
If you have predictable medical costs, want the full balance upfront, or don't qualify for an HSA, a carefully sized FSA still makes sense.
The mistake to avoid is overfunding an FSA.
Guessing high and underspending is how people hand free money back to their employer every December.
Estimate last year's receipts, add a cushion for a dental crown or new glasses, and stop there.
Our take: the HSA is the better deal for most people who can get one, mainly because the money is yours forever and it can double as a retirement stash.
But an FSA beats no account at all, as long as you spend it before the deadline.
Final Thoughts
Run the numbers during open enrollment instead of guessing.