HSA vs 401(k) comes down to one difference: the HSA can be tax-free on the way in, while growing, and on the way out for medical costs, while a 401(k) taxes the money at one end or the other.
Key Takeaways
- The 2026 HSA limit is $4,400 for self-only coverage and $8,750 for family coverage, per IRS Revenue Procedure 2025-19 (IRS Rev. Proc. 2025-19).
- The 2026 401(k) elective deferral limit is $24,500, with an $8,000 catch-up at 50+ and $11,250 at ages 60 to 63 (IRS IR-2025-111).
- 401(k) deferrals are still wages for Social Security and Medicare tax, while HSA money contributed through a cafeteria plan is treated as an employer contribution and generally escapes employment taxes (IRS Topic 424; IRS Publication 969).
- Non-medical HSA withdrawals before 65 owe income tax plus a 20% additional tax; early 401(k) withdrawals before 59½ generally owe a 10% additional tax (IRS Pub. 969; IRS Topic 424).
- HSA eligibility requires HDHP coverage: for 2026, a minimum deductible of $1,700 self-only or $3,400 family (IRS Rev. Proc. 2025-19), and starting in 2026, bronze and catastrophic plans also qualify (IRS Notice 2026-5 release).
- Pre-tax 401(k) balances face required minimum distributions starting at age 73; HSAs have no RMDs and unused balances carry over each year (IRS RMD rules; IRS Pub. 969).
HSA vs 401(k): The 2026 Numbers
Federal figures for tax year 2026. HSA limits include employer contributions; the 401(k) deferral limit does not include employer match. State tax treatment can differ.
What is the difference between an HSA and a 401(k)?
An HSA is a health savings account tied to high-deductible health coverage, while a 401(k) is an employer retirement plan with no health-plan requirement. Both shelter investment growth from tax, but they differ in who can contribute, how much, and what a withdrawal costs.
The HSA is often described as having a triple tax advantage: contributions are deductible or pre-tax, growth is untaxed, and withdrawals for qualified medical expenses are tax-free (IRS Publication 969). A traditional 401(k) defers tax until withdrawal, and a Roth 401(k) taxes money going in but not coming out. Neither 401(k) version offers tax-free treatment at both ends. The two flavors are compared in detail in Roth 401(k) vs traditional 401(k).
Talk With Craig Wear's Team
Craig has helped IRA millionaires save over $1 million each in unnecessary taxes. Find out if a Roth conversion strategy fits your retirement, with no sales pressure and no product pitch.
HSA vs 401(k) side by side
The table lines up the federal rules for 2026. Plan documents and HSA custodians can add their own restrictions, so treat these as the statutory defaults.
| Feature | HSA | 401(k) (traditional) |
|---|---|---|
| 2026 contribution limit | $4,400 self-only / $8,750 family, plus $1,000 at 55+ | $24,500 deferral, plus $8,000 at 50+ or $11,250 at ages 60 to 63 |
| Do employer dollars count toward the limit? | Yes, employer and employee money share one limit | No, the match counts only toward the $72,000 total 415(c) limit |
| Eligibility | HDHP (or, from 2026, bronze or catastrophic plan); no Medicare enrollment | Employer must sponsor a plan; no health-plan condition |
| Federal income tax on contributions | Excluded (payroll) or deductible (direct) | Excluded from taxable wages |
| Social Security and Medicare tax on contributions | Generally none when made through a cafeteria plan | Yes, deferrals remain FICA wages |
| Tax on investment growth | None | None until withdrawal |
| Withdrawals for qualified medical costs | Tax-free at any age | Taxed as ordinary income |
| Non-medical withdrawals | Income tax plus 20% before 65; income tax only at 65+ | Income tax plus 10% before 59½ income tax only after |
| Required minimum distributions | None | Generally from age 73 (75 if born 1960 or later) |
| Portability | Owned by the individual, stays with them | Stays in the employer plan until rolled over |
| At death, non-spouse beneficiary | Full balance taxable in the year of death | Distributed under inherited-account rules |
The HSA limits and HDHP thresholds come from Rev. Proc. 2025-19; the 401(k) limits from IR-2025-111. Year-by-year HSA limit history and the catch-up rules for couples are covered in the HSA as a retirement account, and the 401(k) catch-up tiers in catch-up contributions for 2026.
How are HSA and 401(k) contributions taxed differently?
Both reduce federal income tax in the year of contribution, but only the payroll HSA also avoids Social Security and Medicare tax. The IRS states that 401(k) elective deferrals are excluded from Form W-2 box 1 wages yet are still included as wages subject to Social Security and Medicare withholding (IRS Topic 424).
HSA contributions made by salary reduction through a cafeteria plan are treated as employer contributions, and employer contributions generally are not subject to employment taxes (IRS Publication 969). Contributions made directly to an HSA outside payroll are deducted on the tax return instead, which captures the income tax benefit but not the payroll tax exclusion.
State treatment is a separate question. California, for example, does not conform to the federal HSA rules: residents add back the HSA deduction and pay state tax on HSA interest and dividends as earned (California FTB Schedule CA instructions). Households in non-conforming states may see a smaller net HSA advantage than the federal rules suggest.
Who can contribute to an HSA vs a 401(k)?
A 401(k) is open to any eligible employee of a sponsoring employer, while an HSA depends on the type of health coverage a person has each month. An employee can join a 401(k) regardless of the health plan chosen, but cannot fund an HSA without qualifying coverage.
Qualifying coverage traditionally means a high-deductible health plan; the 2026 deductible and out-of-pocket thresholds are walked through in the 2026 HSA rules guide. Two changes took effect January 1, 2026: bronze and catastrophic plans are now treated as HSA-compatible, and people in certain direct primary care arrangements (fees up to $150 a month, or $300 for family arrangements) can still contribute (IRS release on Notice 2026-5).
The HSA also has an end date the 401(k) does not. Beginning with the first month of Medicare enrollment, the HSA contribution limit is zero (IRS Publication 969). Medicare.gov advises that workers and employers stop HSA contributions 6 months before retiring or applying for Social Security benefits to avoid a tax penalty (Medicare.gov: Working past 65). A worker who stays employed past 65 can usually keep deferring into a 401(k).
How do withdrawal rules compare before and after 65?
The HSA penalizes non-medical spending more heavily before 65, then behaves much like a traditional 401(k) afterward. Before 65, a non-medical HSA withdrawal owes ordinary income tax plus a 20% additional tax; after 65, disability, or death, the additional tax disappears and only income tax applies (IRS Publication 969).
A traditional 401(k) withdrawal is ordinary income at any age, and distributions before 59½ generally add a 10% additional tax unless an exception applies (IRS Topic 424). Exceptions exist, such as separating from service in or after the year of turning 55, and plan rules control how they apply.
The decisive difference is medical spending. Qualified medical expenses come out of an HSA tax-free at any age, while the same bill paid from a pre-tax 401(k) is taxable income first. Which costs qualify, including the age-65 rule allowing Medicare premiums (but not Medigap premiums), is detailed in HSA qualified medical expenses.
How does employer money work in each account?
Employer money is common in both accounts, but it interacts with the limits in opposite ways. In an HSA, the employer contribution reduces how much the employee can add, because one combined limit covers both (IRS Publication 969).
In a 401(k), a match sits on top of the $24,500 employee deferral and counts only toward the $72,000 total annual additions limit. The mechanics of matching formulas are explained in what is a 401(k) match, and the limit interaction in do employer contributions count toward the 401(k) limit.
Vesting is another contrast. Employer 401(k) contributions can follow a vesting schedule, while money already deposited in an HSA belongs to the account owner and remains with them after leaving the job, because the HSA is portable (IRS Publication 969).
What order do people consider when funding both accounts?
There is no single correct sequence; the order depends on the match, health costs, cash flow, and tax bracket. A sequence frequently discussed in planning literature is: contribute enough to the 401(k) to receive any full employer match, then fund the HSA, then direct additional savings back to the 401(k).
The reasoning behind that pattern is that an unclaimed match is money left on the table, and the HSA’s payroll tax exclusion and tax-free medical withdrawals are features no 401(k) offers. It shifts when an HSA charges high fees or limits investment options, when a household expects to spend the HSA every year on current care, or when the person will soon enroll in Medicare.
The same funding-order question for an HSA versus an IRA is addressed in HSA vs Roth IRA. A financial professional can model how these choices play out for a specific household’s cash flow and bracket.
How do an HSA and a 401(k) fit a Roth conversion plan?
They play different roles in retirement tax planning. A large pre-tax 401(k) generates taxable required minimum distributions from age 73 (or 75 for those born in 1960 or later), while an HSA has no RMDs and Roth 401(k) accounts no longer require lifetime distributions (IRS RMD rules).
That is why retirees in a lower-bracket year often consider a Roth conversion of pre-tax 401(k) or IRA dollars, filling a bracket such as the 24% bracket that tops out at $201,775 single or $403,550 married filing jointly in 2026. An HSA cannot be converted to a Roth, but it can quietly support the plan: tax-free HSA withdrawals for Medicare Part B and Part D premiums do not add to taxable income the way a 401(k) withdrawal would. Conversion income can raise those premiums through IRMAA, as shown in the 2026 IRMAA brackets.
One more link between account types: the IRS permits a once-in-a-lifetime qualified HSA funding distribution from an IRA to an HSA, which counts toward that year’s HSA limit (IRS Publication 969). Estate treatment also differs sharply; a non-spouse beneficiary owes tax on the full HSA in the year of death, as explained in inherited HSA rules.
Frequently asked questions
Is an HSA better than a 401(k)?
Neither account is better in every case. The HSA can be tax-free going in, growing, and coming out for qualified medical costs, but it requires qualifying health coverage and has a much lower limit ($4,400 self-only or $8,750 family in 2026). The 401(k) allows $24,500 of deferrals in 2026 and often includes an employer match. Many people with access to both use them together.
Can you contribute to an HSA and a 401(k) in the same year?
Yes. The two accounts have separate limits and separate eligibility rules. An employee covered by a qualifying high-deductible health plan can fund an HSA up to the HSA limit and also defer up to the 401(k) limit in the same year.
Are HSA contributions subject to Social Security and Medicare tax?
HSA contributions made by salary reduction through an employer cafeteria plan are treated as employer contributions and generally are not subject to employment taxes, according to IRS Publication 969. 401(k) deferrals, by contrast, are still included as wages for Social Security and Medicare tax. Contributions made directly to an HSA outside payroll are deductible for income tax but do not avoid payroll tax.
What happens if you use HSA money for non-medical expenses?
Before age 65, a non-medical HSA withdrawal is included in income and owes a 20% additional tax. After 65, or after disability or death, the 20% additional tax no longer applies, but the withdrawal is still taxed as ordinary income, similar to a traditional 401(k) distribution.
Do HSAs have required minimum distributions like a 401(k)?
No. HSA balances carry over from year to year with no required minimum distributions. Pre-tax 401(k) balances generally require distributions beginning at age 73, or 75 for those born in 1960 or later, though a plan may allow a still-working participant to delay.
Do employer HSA contributions count toward the HSA limit?
Yes. Employer and employee HSA contributions share one combined limit, so an employer deposit reduces how much the employee can add. A 401(k) match works differently: it does not count toward the $24,500 employee deferral limit, only toward the $72,000 total annual additions limit.
Can you keep contributing to an HSA after enrolling in Medicare?
No. Beginning with the first month of Medicare enrollment, the HSA contribution limit is zero. Medicare.gov advises stopping HSA contributions 6 months before retiring or applying for Social Security benefits to avoid a tax penalty. Existing HSA money can still be spent on qualified expenses, including Medicare premiums other than Medigap.
Can you roll a 401(k) into an HSA?
No direct 401(k) to HSA rollover exists. The IRS does allow a once-in-a-lifetime qualified HSA funding distribution from an IRA to an HSA, and that amount counts toward the year’s HSA contribution limit.
Methodology: Figures in this article come from primary sources: IRS Revenue Procedure 2025-19 (2026 HSA and HDHP amounts), IRS News Release IR-2025-111 (2026 401(k) limits), IRS Publication 969, IRS Tax Topic 424, IRS required minimum distribution guidance, the IRS release on Notice 2026-5, California Franchise Tax Board instructions, and Medicare.gov. Because this is a Your Money or Your Life topic, anonymous forum anecdotes and unverified secondary summaries were excluded. All amounts reflect federal rules for tax year 2026.
This article is for educational purposes only and is not individualized investment, tax, or legal advice. Consult a qualified professional about your specific situation.
