CalcStack — free, instant, no signup. The interactive calculator loads automatically.
The only account that is tax-free three times.
An HSA is the most tax-favored account in the code: deductible going in, untaxed while it grows, untaxed coming out for medical costs. This calculator projects what maxing it actually becomes — and prices the difference versus investing the same money in a taxable account.
HDHP enrollees use it during open enrollment to see what the triple tax advantage is actually worth in dollars — it converts "HSAs are good" into a five-figure 20-year advantage. The receipt-shoebox strategy FAQ alone changes how people spend.
$4,400 for self-only HDHP coverage and $8,750 for family coverage, plus a $1,000 catch-up at 55+ (IRS Rev. Proc. 2025-19). Your HDHP must have a deductible of at least $1,700 self / $3,400 family and an out-of-pocket max under $8,500 / $17,000. Employer contributions count toward the same cap.
If you can pay medical bills from cash flow, invest the HSA and save the receipts — there is no deadline to reimburse yourself, so a $3,000 ER visit in 2026 can be claimed tax-free in 2046 after two decades of growth. Keep receipts scanned and organized; the audit burden is yours.
It becomes the best of both worlds: medical withdrawals stay tax-free forever, and non-medical withdrawals are simply taxed like a traditional IRA — the 20% penalty disappears at 65. Medicare premiums can even be paid from it. An overfunded HSA is never a problem.