Open enrollment season is here, and two accounts with three similar-looking letters are quietly fighting for your money.
A flexible spending account and a health savings account both let you pay for medical costs with pre-tax dollars.
But the rules around who qualifies, when you can spend the cash, and what happens if you guess wrong are wildly different.
An FSA is the account your employer offers to almost anyone.
You decide during open enrollment how much to set aside, and that full amount is available on day one, even before you have contributed it.
The catch arrives every December 31: use it or lose it.
Miss the deadline and the leftover balance typically goes back to your employer, though some plans allow a small carryover or a short grace period.
An HSA works only if you are enrolled in a high-deductible health plan.
In exchange for that restriction, you get perks an FSA cannot match.
The money rolls over year after year, it follows you when you change jobs, and you can invest the balance once it grows past a threshold.
After age 65, withdrawals for non-medical expenses are taxed but no longer penalized, which makes it a backdoor retirement account for some savers.
The tax math is where paychecks feel the difference.
Say you are in the 22% federal bracket and set aside $3,000.
An FSA or HSA saves you roughly $660 in federal tax, plus state tax in most states and payroll tax on HSA contributions.
That is real money, but only if you actually spend it on eligible care.
Overfunding an FSA is the classic mistake, turning tax savings into forfeited cash.
If you have a choice, the HSA usually wins for long-term planners.
If your high-deductible plan makes you nervous about upfront costs, remember you can pay today's bills from the account and still keep the receipt for later.
If you are stuck with an FSA, estimate low rather than high.
Dental work, glasses, and therapy copays add up fast, but guessing is not a strategy.
One more wrinkle: you generally cannot have both accounts at once.
An HSA demands a high-deductible plan, while an FSA is often paired with traditional coverage.
Some employers offer a limited-purpose FSA for dental and vision alongside an HSA, which lets you stack the two without breaking the rules.
Our take: max out the HSA if you can afford it, invest the balance, and pay small bills out of pocket so the account compounds.
If an FSA is your only option, set a conservative number you know you will spend.
The difference between these two accounts is not three letters.
Final Thoughts
It is whether your money expires or grows.