The HSA as a Retirement Account: How It Compares to Your 401(k) for Medical Costs

Healthcare is one of the largest costs most people face in retirement, and it is also one of the most underplanned. According to Fidelity’s 2025 Retiree Health Care Cost Estimate, a 65-year-old retiring today can expect to spend an average of $172,500 on health care and medical expenses throughout retirement. That figure does not include long-term care.

Medicare helps, but it does not eliminate out-of-pocket costs for premiums, prescriptions, dental care, or vision. Most people focus their retirement planning on a 401(k) or 403(b), then add a Roth IRA if they are eligible. The health savings account rarely gets the same strategic attention.

That is a mistake. When used intentionally, an HSA offers a combination of tax advantages that no other retirement or savings account can match.

Key Details

• The HSA is the only account with a triple tax advantage. Contributions reduce taxable income, growth is tax-free, and withdrawals for qualified medical expenses are tax-free at any age.
• 2026 contribution limits are $4,400 (self-only) and $8,750 (family), plus $1,000 catch-up for those 55 and older.
• There is no deadline for HSA reimbursements. Medical expenses paid out of pocket today can be reimbursed years later, making receipt-keeping a high-value habit.
• Stop contributing at least six months before Medicare enrollment to avoid excess contribution penalties from retroactive Part A coverage.
• New in 2026: Bronze-tier and catastrophic ACA plans now qualify as HSA-eligible, and direct primary care fees up to $150 per month are a qualified expense.

Three Tax Breaks No Other Account Offers

Most tax-advantaged accounts give you one benefit. A traditional 401(k) gives you a deduction today, but withdrawals are taxed in retirement. A Roth IRA gives you tax-free withdrawals, but contributions come from after-tax dollars.

The HSA is different. It offers all three advantages at once: tax-deductible contributions, tax-free growth, and tax-free withdrawals for qualified medical expenses.

A dollar paid from an HSA for a qualified medical expense has never been taxed and never will be. A dollar paid from a traditional 401(k) for the same expense is taxed at whatever rate applies in retirement. For couples in the 24% or 32% bracket, that difference adds up to tens of thousands of dollars over a retirement.

Do You Qualify?

To contribute to an HSA, you must be enrolled in a qualifying high-deductible health plan (HDHP). For 2026, a qualifying plan must carry a minimum annual deductible of $1,700 for self-only coverage or $3,400 for family coverage. The out-of-pocket maximum cannot exceed $8,500 for self-only or $17,000 for family coverage.

A meaningful change took effect in 2026 as part of the One Big Beautiful Bill Act. Bronze-tier and catastrophic plans offered on Affordable Care Act marketplaces now qualify as HSA-eligible, even if they do not meet the standard HDHP deductible minimums. For individuals who purchase their own coverage, this expands access significantly.

How Much You Can Contribute in 2026

The IRS sets HSA contribution limits annually. For 2026:

• Self-only coverage: $4,400
• Family coverage: $8,750
• Catch-up (age 55 or older): Additional $1,000

If both spouses are 55 or older, each can make the catch-up contribution, but they must use separate HSAs. Any employer contributions count toward these limits.

One additional benefit: if your employer takes HSA contributions through payroll deductions, those dollars avoid FICA payroll taxes. This is a savings that IRA and 401(k) contributions do not provide.

The 2026 legislation also made direct primary care arrangement fees (up to $150 per month) a qualified medical expense, expanding how HSA funds can be used.

Comparing the HSA and 401(k) on a $10,000 Medical Expense

Consider two people, both in a 22% federal tax bracket in retirement. Each needs $10,000 for medical expenses.

The first person draws from a traditional 401(k) and pays $2,200 in federal income tax. That leaves $7,800 after taxes.

The second person draws from an HSA and pays nothing. The HSA user keeps the full $10,000.

For a couple who needs $345,000 to cover healthcare costs in retirement (the 2025 Fidelity estimate for a two-person household), the tax savings from using an HSA instead of a traditional retirement account can be substantial. If you work with a tax advisor on retirement income planning, this tradeoff is worth modeling for your specific situation.

Why Paying Medical Bills Out of Pocket Can Build Long-Term Value

Most people treat an HSA as a medical checking account. They contribute, spend the balance on current-year costs, and refill it the next year. This approach works for managing expenses, but it misses the account’s power as a retirement vehicle.

A more effective strategy:

1. Contribute the maximum each year.
2. Invest those funds in a diversified portfolio. Most custodians offer mutual fund or index fund options.
3. Pay current medical expenses out of pocket from regular cash flow.
4. Save every receipt.

Why save receipts? According to IRS Publication 969, there is no deadline for HSA reimbursements. A medical bill paid out of pocket five or ten years ago can still be reimbursed from the HSA, as long as the expense was incurred after the account was opened and you have documentation.

This creates a powerful option. A working professional who pays small medical expenses from cash flow while keeping receipts accumulates a growing pool of documented, unreimbursed expenses. In retirement, those receipts can be submitted to pull tax-free cash from the HSA for any purpose.

The discipline required is straightforward: keep organized records of every out-of-pocket medical expense from the day the HSA is established. A life planning conversation with a CPA can help you model how much this approach could compound in your situation.

Where the HSA Fits in Your Contribution Order

For people with access to multiple retirement accounts, contribution order matters. A common framework:

1. Capture the full employer match first. This is an immediate, guaranteed return. Leaving it on the table is costly.
2. Maximize the HSA. The triple tax advantage makes this the most efficient vehicle for future healthcare costs.
3. Return to your 401(k) or 403(b) and contribute toward the annual max. For 2026, that limit is $24,500 for most workplace plans.
4. If eligible, contribute to a Roth IRA. The 2026 income phase-out begins at $153,000 for single filers and $242,000 for married filing jointly.

Extra Contribution Room After 50

For 2026, the standard 401(k) catch-up limit is $8,000, bringing the total contribution limit to $32,500 for eligible participants. A higher catch-up of $11,250 applies for employees aged 60 through 63 under SECURE 2.0 Act changes.

Roth IRA catch-up remains $1,000, bringing the total Roth limit to $8,000 if income eligibility allows.

If You Have a 457(b), You Have an Extra Advantage

Employees with access to a 457(b) have a particular advantage. Unlike 401(k) and 403(b) plans, 457(b) distributions before age 59½ are not subject to the 10% early withdrawal penalty. This makes the 457(b) useful for bridging early retirement alongside an HSA.

What You Can Pay for With HSA Money in Retirement

After age 65, the HSA becomes more flexible. Qualified medical expenses remain completely tax-free. Non-medical withdrawals are taxed as ordinary income but carry no penalty, making the account function like a traditional IRA for general spending.

Medicare Premiums, Dental, Vision, and Long-Term Care

Per the IRS Form 8889 instructions, HSA funds can pay for:

• Medicare Part A, B, C (Medicare Advantage), and D premiums
• Medicare deductibles, coinsurance, and copayments
• Dental, vision, and hearing aids
• Eligible long-term care insurance premiums up to IRS annual limits

One exception: Medigap (Medicare supplemental) insurance premiums are not a qualified expense. If you do, the withdrawal becomes taxable income and if you’re under age 65, it could also face a penalty.

Retiring Before 65? Your HSA Can Cover the Gap

For early retirees who need coverage before Medicare eligibility, HSA funds can pay for COBRA continuation premiums and health insurance purchased during unemployment. A well-funded HSA provides meaningful flexibility during this transition period.

The Medicare Timing Trap

The most common HSA mistake is continuing to contribute after Medicare enrollment begins. Once you enroll in any part of Medicare, including Part A, your HSA contribution limit drops to zero. Contributions made while covered by Medicare are considered excess and subject to a 6% excise tax for each year the excess remains.

Part A Enrollment Reaches Back Six Months

When you apply for Medicare Part A after age 65, coverage applies retroactively for up to six months. If you contributed to your HSA during that retroactive period, those contributions become excess even if the overlap was unintentional.

For this reason, most advisors recommend stopping HSA contributions at least six months before enrolling in Medicare or claiming Social Security. Claiming Social Security automatically triggers Medicare Part A enrollment retroactively.

Your Existing HSA Balance Is Fine

The restriction applies only to new contributions. Existing HSA balances remain available for qualified medical expenses throughout retirement, regardless of Medicare status.

For those who delay Medicare past 65 because they remain on an employer’s qualifying HDHP, contributions can continue until Medicare coverage begins. The younger spouse in a household also retains contribution eligibility as long as they remain on a qualifying plan.

Colorado Residents: Your HSA Deduction Is Safe

Colorado conforms to the federal tax treatment of HSA contributions. Contributions are deductible for both federal and Colorado state income tax purposes, stacking additional savings on top of the federal benefit.

For Colorado residents working with a Denver or Littleton-area CPA, incorporating HSA contributions into state tax projections is a straightforward extension of annual planning.

State conformity is not universal. California and New Jersey do not allow a state deduction for HSA contributions, and earnings may be subject to state tax. Colorado residents face no such complication.

Steps to Take Now

If you have an HDHP and are not maximizing your HSA, start by increasing contributions to the annual limit. For a 55-year-old with family coverage in 2026, that means $9,750 total ($8,750 plus $1,000 catch-up age 55+). Check your current employer contribution first, as it counts toward the cap.

Review Your HSA Investment Options

Many HSA custodians offer low-cost index funds similar to what you might choose inside a 401(k). The same diversified approach that works for long-term retirement savings works inside an HSA.

Consider Paying Current Expenses Out of Pocket

If your cash flow allows, shift to paying medical expenses out of pocket and let the HSA grow. Establish a receipt-tracking system immediately. The receipts you accumulate over five or ten years can become meaningful tax-free liquidity in retirement.

Talk to Your Advisor About Medicare Timing

If you are within five years of retirement, schedule a conversation with a life planning and tax advisor. Decisions about Medicare timing, HSA wind-down, Social Security claiming, and withdrawal sequencing all interact. Making one decision without considering the others can trigger unnecessary taxes or leave tax-free resources unused.

Working With WhippleWood

WhippleWood serves individuals, families, and business owners across Denver, Littleton, and the surrounding Front Range. Our tax and life planning team works with clients at every stage of retirement preparation, from building the contribution stack in their 40s and 50s to managing withdrawal sequencing once they retire.

If you have questions about how an HSA fits your retirement plan, contact us to get started.