For most people, a 401(k) alone will not provide enough income to maintain their current lifestyle in retirement. It’s a powerful savings tool, but it was designed to work alongside Social Security and other savings, not replace them. Whether your 401(k) can do the heavy lifting depends on how much you contribute, how long you invest, what your employer matches, and how much you’ll actually need to spend once you stop working.
How Much Retirement Income You Actually Need
A common benchmark is that you’ll need 70% to 80% of your pre-retirement income each year to live comfortably. If you earn $80,000 before retiring, that means roughly $56,000 to $64,000 annually. Some expenses drop in retirement (commuting, professional wardrobe, payroll taxes), but others rise significantly, especially healthcare.
A healthy 65-year-old couple retiring today can expect to spend roughly $662,000 on healthcare over their lifetime, according to projections from HealthView Services. That figure jumps to over $955,000 when adjusted for future medical inflation, which has been running at about 5.8% per year. Medicare covers a portion, but premiums, copays, dental, vision, and long-term care add up fast. Healthcare alone can consume a massive share of your retirement budget, which means your savings need to stretch further than many people expect.
What a 401(k) Can Realistically Produce
The 2026 employee contribution limit for a 401(k) is $24,500. If you’re 50 or older, you can add a catch-up contribution of $8,000, bringing your personal cap to $32,500. Workers aged 60 through 63 get an even higher catch-up limit of $11,250 instead of $8,000, pushing their maximum to $35,750.
Those limits sound generous, but most workers don’t come close to maxing them out. The median 401(k) balance for Americans approaching retirement (ages 55 to 64) tends to hover in the low six figures. Even a $500,000 balance, which puts you well ahead of most savers, generates only about $20,000 per year if you follow the common 4% withdrawal guideline. That’s a starting point, not a full income.
Employer matching can help significantly. If your company matches 50 cents on each dollar up to 6% of your salary, that’s free money compounding over decades. But even with a match, the math gets tight if your 401(k) is your only retirement account. Someone earning $80,000 who contributes 10% annually with a 4% match starting at age 30 might accumulate around $1.2 million to $1.5 million by age 65, assuming roughly 7% average annual returns. That sounds like a lot, but at a 4% withdrawal rate it produces $48,000 to $60,000 per year, before taxes.
Taxes Take a Bigger Bite Than You Think
If you have a traditional 401(k), every dollar you withdraw counts as ordinary income and gets taxed at your federal rate for that year. A $50,000 withdrawal isn’t $50,000 in your pocket. Depending on your total income (including Social Security), you could owe 12%, 22%, or more in federal taxes, plus state income tax if your state levies one. That $50,000 withdrawal might net you $40,000 or less in spendable cash.
A Roth 401(k) works differently. You pay taxes on contributions now, but withdrawals in retirement are completely tax-free, including all the investment growth. If your employer offers a Roth option, splitting contributions between traditional and Roth gives you flexibility to manage your tax bill in retirement. Having both types of accounts lets you pull from the Roth in years when you want to keep your taxable income low, and from the traditional account in years when you have more room in a lower bracket.
What Social Security Actually Covers
Social Security was never meant to replace your full paycheck. For a medium earner, it replaces roughly 40% of pre-retirement income. Higher earners see an even smaller replacement rate, closer to 35%, because the benefit formula is progressive. Lower earners fare better percentage-wise, with replacement rates around 56%, but the dollar amounts are still modest.
Here’s where it gets uncomfortable: healthcare inflation is outpacing Social Security cost-of-living adjustments by a wide margin. Social Security COLAs have averaged around 2.4% in recent projections, while healthcare costs have been rising at 5.8%. HealthView Services estimates that 84% of a healthy couple’s lifetime Social Security benefits will go toward healthcare expenses. For younger workers, that share climbs above 100%, meaning Social Security won’t even cover medical costs, let alone rent, food, and everything else.
So if Social Security handles healthcare (barely), your 401(k) needs to cover most of your remaining living expenses. That’s a heavy load for one account.
Filling the Gap With Other Savings
The strongest retirement plans layer multiple income sources. Your 401(k) is the foundation, but consider building on top of it.
- IRA contributions: The 2026 IRA limit is $7,500. A traditional or Roth IRA gives you another tax-advantaged bucket. A Roth IRA is especially valuable because withdrawals are tax-free and there are no required minimum distributions during your lifetime.
- Taxable brokerage accounts: Once you’ve maxed out tax-advantaged space, a regular investment account has no contribution limits. You’ll pay taxes on dividends and capital gains, but you also get full flexibility to withdraw anytime without penalties.
- Health Savings Account (HSA): If you have a high-deductible health plan, an HSA lets you contribute pre-tax dollars, grow them tax-free, and withdraw tax-free for medical expenses. After age 65, you can use HSA funds for any purpose (you’ll just pay income tax on non-medical withdrawals, similar to a traditional 401(k)).
Even small amounts in these additional accounts compound meaningfully over 20 or 30 years. The goal isn’t perfection in any single account. It’s having enough total savings across all accounts to bridge the gap between Social Security and what you actually spend.
How to Tell If You’re on Track
A rough rule of thumb: aim to have one times your annual salary saved by age 30, three times by 40, six times by 50, and eight to ten times by 65. If you earn $100,000 at retirement, that means $800,000 to $1 million in total savings. These are ballpark figures, and your actual number depends on your spending, where you live, whether you’ll have a mortgage, and how early you retire.
Run the numbers with your own situation. Add up your projected Social Security benefit (you can check your estimate at ssa.gov), your expected 401(k) balance at retirement, any other savings, and any pension or rental income. Compare that total annual income to 70% to 80% of your current earnings. If there’s a gap, you have time to close it by increasing your contribution rate, even by just 1% or 2% per year. Small bumps in savings rate during your working years have an outsized effect on your final balance thanks to compound growth.
If you’re within a decade of retirement and your 401(k) is your only significant savings, the math gets harder. You can take advantage of catch-up contributions, delay Social Security to increase your monthly benefit (each year you wait past 62 up to age 70 boosts your check by about 6% to 8%), and reduce your expected spending by paying off debt or downsizing housing. These levers won’t close every gap, but they can make a meaningful difference.