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HSA Growth Calculator
The triple tax advantage is easy to praise and hard to picture. This HSA growth calculator puts numbers on it — your balance at retirement, the tax you save, and how far investing your HSA beats spending it or using a taxable brokerage.
See how this works on a $4,750-a-year HSA — 3 real examples
Projected HSA balance at retirement
$0
Pre-tax inTax-free growthTax-free out for medical
Total tax savings
$0
Tax-free growth
$0
Invest vs spend gap
$0
HSA vs taxable
$0
Balance at retirement: invest and grow vs spend as you go
Tax-free HSA vs a taxable brokerage over time
IRS HSA limits & data source
Last reviewedYear-by-year HSA growthContributions, the invested balance, the spend-path balance and a taxable brokerage
| Age | Contributed to date | HSA (invested) | HSA (spending medical) | Taxable brokerage |
|---|
How your HSA balance and tax savings are calculated
Your current balance and every year's total contribution — yours plus your employer's — are grown at your expected return with annual compounding, the standard future-value of a starting sum plus a contribution stream:
HSA balance = balance·(1 + r)n + C·((1 + r)n − 1) / r
where r is your annual return, n the years to retirement (retirement age minus current age) and C the combined annual contribution. Because qualified medical withdrawals are never taxed, the full return compounds — that’s the invest-and-grow path and the headline balance. The spend path runs the same growth but subtracts your annual medical spending from the account each year; the difference between the two ending balances is the invest-vs-spend gap.
Total tax savings is a flat, honest figure — your contribution × years × (marginal rate + FICA) — where FICA is added only if you turn on payroll contributions and enter a rate. Employer money is already pre-tax, so it is excluded from your deduction. There is no bracket math and no tax-liability calculation anywhere here: every tax number comes straight from the flat rates you enter.
The taxable-brokerage comparison invests the same money post-tax and applies your marginal rate as an annual drag on the return — it grows at return × (1 − marginal rate), the standard approximation for yearly taxes on interest, dividends and turnover. The gap between the tax-free HSA and that account is your HSA advantage. After age 65 the 20% penalty on non-medical withdrawals ends, so beyond qualified medical use the HSA behaves like a traditional IRA (withdrawals taxed as ordinary income) — this projection reports the pre-tax balance you would have available at that point.
The 2026 HSA contribution limits shown are a dated, informational reference from the IRS (self-only $4,400, family $8,750, plus an age-55+ catch-up of $1,000), reviewed July 2026. They are never enforced as a cap — the calculator only flags when your entered contributions exceed them, and limits change, so confirm the current figure with the IRS.
One HSA, three ways the years get used
The same $4,750 a year — left invested, tapped for medical bills, or started fifteen years late. The years do most of the work.
Left invested from 35 to 65
at age 65$463,913
- Thirty years of $4,750 deposits total $142,500; tax-free growth adds $319,413 on top.
- Those contributions trim $28,800 off tax bills along the way at the 24% rate.
- In a taxable brokerage the same money ends near $260,648 — the HSA finishes $203,265 ahead.
Left alone for thirty years, $144,500 in becomes close to half a million — none of it taxed.
Load this example (opens in a new tab)$3,000 of medical bills a year
at age 65$180,531
- Every withdrawal comes out tax-free, exactly as designed — and stops compounding the moment it leaves.
- The deduction is untouched: contributions still save $28,800 in tax either way.
- Covering those bills from pocket money instead would leave $283,382 more in the account at 65.
Ninety thousand dollars withdrawn over the years ends up costing $283,382 in balance.
Load this example (opens in a new tab)Opened at 50 instead of 35
at age 65$124,881
- Half the money goes in — $71,250 against $142,500 — yet barely a quarter of the balance comes out.
- Growth manages $51,631 in fifteen years, where the thirty-year run earned $319,413.
- The edge over a taxable brokerage shrinks to $41,772.
The late start saves fifteen years of contributions and gives up most of the compounding.
Load this example (opens in a new tab)Illustrations only, not financial advice. Your own rate, taxes and insurance will differ — check with a qualified financial advisor before acting on any of this.
Turning an HSA into a retirement account, in plain English
- The triple tax break is unmatched. Pre-tax in, tax-free growth, and tax-free out for medical — no 401(k) or Roth does all three, which is why an HSA is often the most tax-efficient account you own.
- Invest, don’t just spend. Paying medical bills out of pocket and leaving the HSA invested keeps it compounding — the invest-vs-spend gap above shows how much larger the balance grows that way.
- Every contribution saves tax today. Your own contributions cut this year’s taxable income at your marginal rate, and payroll contributions skip FICA on top — a guaranteed return before any market gains.
- After 65 it doubles as an IRA. The penalty on non-medical withdrawals disappears; take medical costs tax-free or anything else at ordinary income tax, just like a traditional IRA.
- Mind the limit, add the catch-up. Contributions above the annual IRS limit aren’t deductible; at 55+ you get an extra $1,000 of room — toggle it to fold that into the reference limit shown.
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Frequently asked questions
What is an HSA's triple tax advantage?
A Health Savings Account is taxed favorably three separate times. Contributions go in pre-tax (or are deductible), lowering this year’s taxable income; the balance grows without any annual tax on interest, dividends or gains; and withdrawals for qualified medical expenses come out completely tax-free. No other account — not a 401(k), not a Roth IRA — offers all three at once. This calculator quantifies each leg using your own numbers.
Can I invest the money in my HSA?
Yes. Most HSA providers let you invest the balance above a small cash threshold in index funds, ETFs or mutual funds, exactly like a brokerage or IRA. That is what turns an HSA from a spending account into a long-term retirement vehicle. This tool models the invest-and-grow path — leaving the balance invested at your expected return — against simply spending each year’s medical costs from the account, so you can see the gap that investing creates.
How much should I contribute to my HSA?
A common strategy is to contribute the maximum you can afford — up to the annual IRS limit shown on this page — and pay current medical bills out of pocket so the HSA stays invested. Every employee dollar you contribute saves your marginal tax rate (plus FICA if it runs through payroll) immediately, and then grows tax-free. Use the contribution slider to see how the balance and tax savings respond; even a few thousand dollars a year compounds substantially over decades.
How does an HSA work as a retirement account after 65?
Once you turn 65 the 20% penalty on non-medical withdrawals disappears. You can still take qualified medical withdrawals tax-free forever, but you may also withdraw for anything else and simply pay ordinary income tax on it — the same treatment as a traditional IRA. That makes an HSA a flexible retirement account with an extra tax-free lane for the healthcare costs almost everyone faces in retirement. This calculator projects the balance you would have available at that point.
Should I spend or invest my HSA funds?
If you can cover current medical bills from cash flow, leaving the HSA invested usually wins by a wide margin because the balance keeps compounding tax-free. The invest-vs-spend gap on this page shows exactly how much larger the account grows when you pay out of pocket instead of drawing it down each year. Spending from the HSA is still perfectly valid and tax-free — it just forgoes the long-term growth.
What is the HSA catch-up contribution for people 55 and older?
Account holders age 55 and up can contribute an extra $1,000 per year on top of the standard self-only or family limit. If both spouses are 55+, each can make the catch-up but only into their own HSA. Toggle the 55+ catch-up option to fold that extra room into the informational limit shown here. As always, the limits on this page are a dated reference (2026 figures, reviewed July 2026) — not a cap the calculator enforces.
How is my HSA vs taxable-account advantage calculated?
The HSA grows your contributions at the full expected return with no annual tax. The taxable-brokerage comparison invests the same money post-tax and applies your marginal rate as a yearly drag on the return — the standard approximation for taxes on interest, dividends and turnover. The difference between the two ending balances is the HSA advantage. It is an illustration driven purely by the rates you enter, not a tax-liability calculation.
Disclaimer: these calculators are educational tools, not financial advice. They model your inputs with published formulas, but they cannot know your full situation — for decisions with real stakes, talk to a qualified professional. Formulas and defaults last reviewed .