Fidelity's 2026 estimate is that a 65-year-old retiring this year will spend an average of $185,500 on health care over the rest of their life — about $371,000 for a couple retiring together. That figure has been accelerating: roughly 4% growth in 2024, 5% in 2025, and 7.5% this year.
Most retirement plans treat that number as a line item to be funded out of taxable IRA withdrawals. There is a better container for it, and it happens to be the single most tax-efficient account in the entire code. The problem is that almost nobody uses a Health Savings Account the way it was designed to be used — and the ones who do often walk straight into a Medicare rule that converts years of careful saving into an excise tax.
The Triple Tax Advantage Is Not Marketing
Every other retirement account makes you choose when to pay tax. A traditional 401(k) deducts now and taxes the withdrawal. A Roth IRA taxes the contribution and frees the withdrawal. You pick your poison.
An HSA refuses the trade entirely:
- Deductible going in. Contributions are excluded from income (payroll) or taken as an above-the-line deduction (direct).
- Tax-free while it grows. Invested balances compound with no annual tax drag and no tax on rebalancing.
- Tax-free coming out. Withdrawals for qualified medical expenses are never taxed, at any age.
| Traditional 401(k) | Roth IRA | HSA | |
|---|---|---|---|
| Contribution | Deductible | After-tax | Deductible |
| Growth | Tax-deferred | Tax-free | Tax-free |
| Qualified withdrawal | Ordinary income | Tax-free | Tax-free |
| Payroll tax on contributions | Yes | Yes | No (via payroll) |
| Required minimum distributions | Yes | No | No |
The fourth advantage nobody counts
Contributions made by payroll deduction through an employer's Section 125 cafeteria plan also avoid Social Security and Medicare payroll taxes — a break no 401(k), IRA, or Roth contribution can match. For most earners that's the full 7.65%: 6.2% Social Security plus 1.45% Medicare.
The 6.2% piece stops at the Social Security wage base, $184,500 in 2026. On wages above that, only the uncapped 1.45% Medicare portion is still being saved — so a high earner gets a real but smaller break than the headline number suggests.
Either way, this is why funding an HSA at work beats writing a check to it later. A direct contribution still gets you the income-tax deduction, but the FICA savings only exist through payroll.
2026 Contribution Limits and Eligibility
The IRS set the 2026 figures in Revenue Procedure 2025-19. To contribute at all, you must be covered by a qualifying high-deductible health plan (HDHP) and have no other disqualifying coverage.
| 2026 amount | Self-only | Family |
|---|---|---|
| HSA contribution limit | $4,400 | $8,750 |
| HDHP minimum deductible | $1,700 | $3,400 |
| HDHP out-of-pocket maximum | $8,500 | $17,000 |
Anyone age 55 or older by year-end may add a $1,000 catch-up contribution.
The catch-up is per person, not per plan
A married couple on a single family HDHP shares the $8,750 family limit, but each spouse's $1,000 catch-up must go into an HSA in their own name. If only one spouse has an account, the household forfeits the other $1,000 every year. Opening a second HSA for the other spouse is usually a ten-minute fix worth $1,000 of deductible contributions annually.
What Changed for 2026
The One Big Beautiful Bill Act, enacted in July 2025, meaningfully widened who can use an HSA starting January 1, 2026. Three changes matter:
- Bronze and Catastrophic marketplace plans are now HSA-eligible. Any bronze or catastrophic plan bought through an ACA Exchange is treated as HSA-compatible even if it doesn't meet the usual deductible and out-of-pocket tests. That opens HSAs to roughly 7.3 million people — about 30% of marketplace enrollees — who previously couldn't contribute.
- Direct primary care no longer disqualifies you. A DPC membership used to be "other coverage" that killed HSA eligibility. From 2026 you can hold one and still contribute, and you can pay the monthly fee from the HSA, so long as the fee doesn't exceed $150/month for one person or $300/month for more than one.
- The telehealth safe harbor is permanent. Pre-deductible telehealth and remote care no longer break eligibility.
The bronze-plan change is the big one for early retirees. If you retire at 60 and buy marketplace coverage to bridge the gap to 65, you may now be able to keep funding an HSA during exactly the years you have the most control over your taxable income.
The Retirement Play: Stop Spending It
Here is where nearly everyone leaves money on the table. Most people treat an HSA as a spending account — money goes in, the dentist bill comes out, the balance hovers near zero. Used that way it's a modest tax break on routine care.
Used as a retirement account, it's the best one you have. The mechanics that make this work:
Invest the balance. Most custodians let you move anything above a small cash threshold into mutual funds or ETFs. A balance that sits in cash for twenty years earns you the deduction and nothing else.
Pay current medical bills out of pocket. If cash flow allows, pay today's expenses from a taxable account and let the HSA compound untouched.
Keep the receipts — forever. There is no deadline for reimbursing yourself. A qualified expense incurred in 2026 can be reimbursed tax-free from your HSA in 2046, provided the expense was incurred after the account was established and was never deducted or reimbursed elsewhere. Two decades of growth accrue tax-free, and you hold a standing right to withdraw that amount tax-free at any moment.
There are no RMDs. Unlike a traditional IRA, nothing forces money out of an HSA at 73 or 75. It can be the last account you touch — or the one you draw on precisely when a medical bill lands.
Why the receipt strategy is really a liquidity strategy
A stack of unreimbursed receipts functions as a tax-free emergency fund that happens to be invested for growth. Need $30,000 unexpectedly at 70? If you've accumulated $30,000 of documented, never-reimbursed medical expenses, you can pull it from the HSA tax-free — no ordinary income, no bump to your IRMAA tier, no tax torpedo effect on your Social Security. The same $30,000 from a traditional IRA could do all three.
The Medicare Trap
This is the part that costs people real money, and it's the reason HSA planning belongs in the same conversation as Medicare enrollment and Social Security timing.
Enrolling in any part of Medicare — including premium-free Part A — permanently ends your ability to contribute to an HSA. You can still spend the balance. You can still let it grow. But no new money goes in, ever.
Two wrinkles turn that rule into a trap.
Claiming Social Security auto-enrolls you in Part A
You don't have to sign up for Medicare to lose HSA eligibility. Turning on your Social Security benefit does it for you — Part A enrollment is automatic and, in practice, not refusable while you're collecting benefits. Someone who claims at 65 while still working under an employer HDHP has quietly ended their HSA contributions without ever making a Medicare decision.
Part A is backdated up to six months
If you enroll in Medicare after age 65, Part A coverage is generally made retroactive up to six months — never earlier than the month you turned 65, but up to half a year back. You are then treated as having been enrolled in Medicare during that entire window.
Every HSA contribution made in those retroactive months becomes an excess contribution, subject to a 6% excise tax for each year it remains in the account.
How this plays out in practice
A 67-year-old still working with an HDHP contributes the full $5,400 for 2026 ($4,400 plus the $1,000 catch-up) through payroll across the year. In November he retires and enrolls in Medicare. Part A is backdated six months to May.
That leaves him an eligible individual for just four months — January through April. His real 2026 limit is four-twelfths of $5,400, or $1,800. The remaining $3,600 is an excess contribution: taxable income, plus a 6% excise tax charged again every year until it's corrected.
Nothing he did was careless; he simply didn't know Part A reaches backward.
The fix is calendar arithmetic. If you plan to work past 65 and keep funding an HSA, stop contributions at least six full months before the month you enroll in Medicare or claim Social Security. Prorate your final year's contribution to the months you were actually eligible. Coordinate the HSA cutoff, the Medicare enrollment date, and the Social Security claiming decision as one decision rather than three.
What HSA Money Can Pay For Once You're on Medicare
Losing the ability to contribute is not the same as losing the account. After 65 the HSA becomes genuinely flexible.
Medicare premiums — mostly. Part B, Part D, and Medicare Advantage (Part C) premiums are qualified expenses payable tax-free from an HSA. Medigap premiums are not. That exclusion surprises people every year: a Medigap policy is the one Medicare-adjacent premium your HSA can't cover tax-free.
Long-term care insurance premiums, up to an annual age-based cap set by IRC §213(d)(10). For 2026:
| Attained age at year-end | Maximum eligible premium |
|---|---|
| 40 or under | $500 |
| 41–50 | $930 |
| 51–60 | $1,860 |
| 61–70 | $4,960 |
| 71 and older | $6,200 |
Those caps rise steeply with age, which pairs well with long-term care planning — the HSA can absorb a meaningful share of a traditional LTC policy premium in exactly the years the premium is largest.
Anything at all, if you're willing to pay tax. After 65, non-medical withdrawals lose the 20% penalty and are simply taxed as ordinary income. At that point the HSA behaves like a traditional IRA with no RMDs — a worst case that is still perfectly respectable.
The Tax-Planning Angle Advisors Miss
Qualified HSA withdrawals do not appear in your income at all. Not in AGI, not in MAGI, not in provisional income. That makes the HSA the only meaningful source of retirement cash flow that is completely invisible to the income-tested systems that punish retirees:
- It doesn't push you over an IRMAA bracket, where a single dollar of MAGI can cost hundreds per year in Medicare surcharges
- It doesn't drag Social Security benefits into taxation
- It doesn't crowd out room you'd rather use for Roth conversions
For a retiree managing income to the top of a bracket, an HSA is the release valve. Health expenses are precisely the category most likely to produce a large, unplanned, badly timed withdrawal — the kind that wrecks a conversion plan or trips an IRMAA tier two years later. Funding those expenses from a source that never touches MAGI protects the rest of the withdrawal sequence.
Where the HSA Fits in Your Funding Order
For most households still working, the priority stack looks like this:
- 401(k) up to the full employer match — an immediate guaranteed return nothing else matches
- HSA to the maximum — the only triple-tax-free dollar available, plus the FICA break via payroll
- Back to the 401(k) to the annual limit, choosing pre-tax or Roth on bracket expectations
- Roth IRA or taxable with what's left
The HSA outranks additional 401(k) dollars because of what those dollars become. A pre-tax 401(k) dollar is a dollar you'll eventually pay income tax on and eventually be forced to withdraw. An HSA dollar spent on health care — the one expense you can be nearly certain of having — is never taxed and never forced out.
The Estate Weak Spot
The HSA has one genuine flaw, and it is sharp.
If your spouse is the beneficiary, the account becomes their own HSA. Nothing is taxed, nothing changes.
If anyone else is the beneficiary, the account stops being an HSA on the date of death and its entire fair market value becomes ordinary income to that beneficiary in that year. There is no ten-year window like the inherited IRA rules. There is no stretch. A $200,000 HSA left to an adult child in her peak earning years lands on a single tax return, all at once.
Spend the HSA, leave the Roth
This flips the usual "spend taxable first, leave the tax-free accounts for heirs" instinct. A Roth IRA is a superb inheritance. An HSA is a terrible one. If you're choosing which tax-free account to draw down in your seventies and eighties, spend the HSA and preserve the Roth — you get identical tax treatment while you're alive, and vastly better treatment for your heirs.
Two States Don't Play Along
California and New Jersey do not conform to the federal HSA rules. In both states, contributions are not deductible on the state return and earnings inside the account are subject to state income tax. The federal triple advantage is intact; the state layer simply isn't there.
It rarely changes the answer — the federal benefit dominates — but it does mean California and New Jersey residents should expect state tax reporting on HSA earnings, and may prefer simpler, lower-turnover investments inside the account to keep that reporting manageable.
Getting Started
The HSA is the most under-used account in retirement planning, and the gap between using one well and using one badly is enormous. Used as a checking account for co-pays, it saves you a few hundred dollars a year in tax. Used as an invested, receipt-documented, never-touched retirement account, it becomes the only pool of money you can spend in retirement without the tax code noticing.
Three things are worth doing now:
- If you're eligible and not maxing it, fix that — through payroll if at all possible, and make sure both spouses have their own account if either is 55 or older.
- If you're within a few years of 65 or of claiming Social Security, map the calendar. Count six months backward from your likely Medicare enrollment and mark the date your contributions must stop. This is the single most expensive detail in the entire topic.
- If you already have a balance, check whether it's invested. A large HSA sitting in cash has the tax treatment of a great account and the returns of a savings account.
Because the right answer depends on your health coverage, your retirement date, your Social Security timing, and the bracket you'll be managing to, this is worth modeling alongside the rest of your income plan rather than in isolation — the HSA decision and the Medicare decision are the same decision.
This article is for educational purposes only and does not constitute tax, legal, or financial advice. HSA contribution limits, HDHP thresholds, eligible long-term care premium caps, and Medicare enrollment rules are governed by federal rules that change annually, and state tax treatment varies. The 2026 figures cited come from IRS Revenue Procedure 2025-19 (HSA and HDHP limits), Revenue Procedure 2025-32 (long-term care premium caps), and IRS Topic No. 751 (payroll tax rates and the Social Security wage base). Consult a qualified tax professional and confirm current amounts with the IRS and the Social Security Administration before acting on this information.