How long $100,000 lasts in retirement depends almost entirely on your other income sources and where you live. If it’s your only money and you have no Social Security or pension, $100,000 covers roughly one to two years of basic living expenses in most parts of the country. If it supplements Social Security, it can stretch much further, potentially five to ten years or more depending on your spending and whether you keep it invested.
The Math Without Other Income
The average single retiree in the U.S. spends between $50,000 and $60,000 a year on housing, food, healthcare, transportation, and other essentials. At that burn rate, $100,000 disappears in under two years. In the most expensive areas, the picture is even grimmer. In Hawaii, for example, $100,000 covers less than 12 months of typical retirement spending. In lower-cost parts of the country, you might stretch it closer to two years, but not much beyond that.
These figures assume you’re paying for everything out of pocket with no other income stream. Very few retirees are actually in that situation, which is why the real answer requires looking at the gap between what you receive each month and what you spend.
How Social Security Changes the Picture
The average retired worker will receive about $2,071 per month in Social Security benefits in 2026, which works out to roughly $24,850 a year. If your annual expenses are $48,000, Social Security covers about half, leaving a gap of around $23,150 per year. At that rate, $100,000 fills the gap for a little over four years.
If your expenses are lower, say $36,000 a year in a modest-cost area, the annual gap drops to about $11,150. Now that same $100,000 lasts close to nine years. And if you delay Social Security to age 70, your monthly benefit could be 24% to 32% higher than at full retirement age, shrinking the gap even further.
The formula is straightforward: subtract your guaranteed monthly income (Social Security, pension, annuity) from your monthly expenses. Whatever’s left is what $100,000 has to cover. Divide $100,000 by that annual shortfall, and you have your answer in years.
Investment Returns Can Add Years
If you leave $100,000 sitting in a savings account earning minimal interest, inflation eats away at its purchasing power every year. But if you keep it partially invested, even conservatively, the money works harder.
A balanced portfolio of stocks and bonds has historically returned around 5% to 7% annually over long periods, though returns vary year to year. A retiree withdrawing 4% of their balance in the first year (about $4,000) and adjusting for inflation each year after that could reasonably expect the money to last 25 to 30 years based on historical market performance. That’s the logic behind the well-known “4% rule,” originally designed for larger portfolios but applicable as a guideline for any lump sum.
The catch with $100,000 is that 4% only gives you $4,000 a year, or about $333 a month. That’s helpful as a supplement, but it won’t cover major expenses on its own. If you need to withdraw $10,000 or $15,000 a year, you’re pulling 10% to 15% annually, and the portfolio will likely be depleted in 8 to 12 years depending on market conditions.
Taxes Reduce Your Spendable Amount
Where your $100,000 is held matters. If it’s in a traditional 401(k) or traditional IRA, every dollar you withdraw counts as ordinary taxable income. At lower income levels, you’ll likely fall into the 10% or 12% federal tax bracket, meaning $100,000 in the account translates to roughly $88,000 to $90,000 in spendable money after federal taxes. State income taxes, if your state has them, reduce that further.
If the money is in a Roth IRA or Roth 401(k), qualified withdrawals are federally tax-free, so you keep the full $100,000. Money in a regular taxable brokerage account falls somewhere in between: you owe taxes only on gains, not on the original amount you invested.
One more thing to watch: if you withdraw from a traditional retirement account before age 59½, you’ll typically owe a 10% early withdrawal penalty on top of income taxes. There are exceptions, including the “rule of 55,” which lets you take penalty-free withdrawals from a 401(k) if you leave that employer during or after the year you turn 55.
Healthcare Costs Take a Big Bite
Healthcare is one of the largest expenses retirees face, and it can consume a surprising share of a $100,000 nest egg. If you’re 65 or older and on Medicare, your baseline costs in 2026 include a Part B premium of $202.90 per month, plus a Part D prescription drug premium averaging about $34.50 per month. That’s nearly $2,850 a year in premiums alone before you pay a single copay or fill a single prescription.
Add in the Part B deductible of $283, the Part D deductible of up to $615, and the 20% coinsurance you owe on most Medicare-approved services, and a retiree with moderate health needs can easily spend $5,000 to $7,000 a year on healthcare. A serious hospitalization triggers additional costs: the Part A deductible is $1,736 per benefit period, with daily coinsurance charges of $434 for extended stays.
Many retirees buy supplemental Medigap insurance to limit these out-of-pocket costs, but those policies carry their own premiums, often $150 to $300 or more per month depending on the plan and your age. If you retire before 65 and don’t yet qualify for Medicare, health insurance through the marketplace can run $500 to $1,000+ per month, which alone could consume $6,000 to $12,000 a year from your savings.
A Realistic Scenario
Here’s what a typical situation looks like. A 65-year-old retiree collects $2,071 per month in Social Security, keeps $100,000 in a traditional IRA invested in a balanced fund, and lives in a moderate-cost area with monthly expenses of $3,200 (about $38,400 per year).
Social Security covers $24,850 of that, leaving a $13,550 annual gap. After accounting for taxes on IRA withdrawals at an effective rate of around 10% to 12%, the retiree needs to pull roughly $15,000 to $15,500 from the IRA each year to net $13,550. With modest investment returns partially replenishing the account, the $100,000 lasts approximately seven to eight years, getting this retiree to their early to mid-70s.
If that same retiree can trim expenses to $2,800 a month, the gap shrinks and the money stretches past ten years. If unexpected medical costs or home repairs hit, it could run out in five or six.
Ways to Make It Last Longer
Controlling housing costs has the single biggest impact. Housing typically accounts for 30% to 35% of a retiree’s budget. Downsizing, relocating to a lower-cost area, or paying off a mortgage before retirement can free up thousands of dollars a year, directly extending how long your savings hold out.
Delaying Social Security is another powerful lever. Every year you wait past your full retirement age (up to age 70), your benefit increases by about 8%. A retiree who can live on $100,000 for a few years while delaying Social Security from 62 to 67 could see their monthly benefit jump by 30% or more, permanently reducing the gap the savings need to fill.
Part-time work, even modest earnings of $500 to $1,000 a month, dramatically changes the equation. That extra income means pulling less from savings, giving investments more time to grow and pushing the depletion date years into the future.
Finally, keeping a portion of the $100,000 invested rather than moving it all to cash gives the money a chance to grow. A 60/40 stock-and-bond mix provides some growth potential while limiting the kind of dramatic swings that would be devastating for a small portfolio you’re actively drawing from.