FSA vs HSA — they're not interchangeable
HSA requires a high-deductible plan, rolls over forever, and invests. FSA works with any plan but expires. If you have the HSA option, it dominates — the FSA is the consolation prize for PPO enrollees, and the dependent-care FSA is its best use (daycare is a guaranteed spend).
- • The full health FSA election is available day one — even before you've contributed.
- • Stock the eligible-items list: sunscreen, first aid, contacts solution all count.
- • Run out the carryover before March or it's gone.
Related guides
Long-form playbooks on the same topic, written by the RevenueLab editorial team.
FAQ
How much should I put in my FSA?
Only your guaranteed floor: recurring prescriptions, planned dental work, glasses, therapy sessions. A common safe election is last year's actual FSA-eligible spend minus 10–15%.
What happens to unused FSA money?
It's forfeited to your employer, minus any carryover (~$640) or grace period (2.5 months) your plan offers — plans can offer one or neither, not both.
Can I have an FSA and an HSA?
Not a general health FSA — it disqualifies HSA contributions. A limited-purpose FSA (dental and vision only) is allowed alongside an HSA and is a smart pairing.
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