An HSA is often called triple tax advantaged: contributions reduce taxable income, the balance grows tax-free, and qualified withdrawals are tax-free too — a combination no other common U.S. account offers all at once.
How it works
Each year’s contribution is added to a balance that grows at the expected return, compounding the same way a retirement account does. Separately, the contributions are multiplied by a marginal tax rate to estimate the tax saved by contributing pre-tax rather than after-tax dollars.
Why this doesn’t enforce the IRS contribution limit
The actual limit depends on coverage type (self-only or family), age (a catch-up amount applies at 55+), and is prorated for a partial year of HDHP eligibility — details this calculator doesn’t ask for. It projects whatever contribution is entered rather than validating it against the current limit.
How to use this calculator
- Enter the current balance, if any, and the annual contribution planned.
- Enter the number of years to project, expected return, and marginal tax rate.
Frequently asked questions
What happens to HSA funds if they’re not spent on medical expenses?
They stay invested and carry over indefinitely — unlike an FSA, an HSA has no “use it or lose it” deadline.
Can HSA funds be used for anything after retirement?
After 65, non-medical withdrawals are taxed like a traditional retirement account withdrawal (income tax, no penalty) — medical withdrawals stay tax-free at any age.
Does this account for investment fees inside the HSA?
No — the expected return entered should already reflect fees if you want a more realistic projection.
