Figuring out how long will retirement money last is one of the most common financial questions in America — and one of the least understood. According to the Social Security Administration, a 65-year-old man today can expect to live to about 84, while a 65-year-old woman can expect to reach about 87.
That means your savings may need to cover 20 to 25 years of expenses, or more.
The problem is that most people estimate how long will retirement money last using rough guesses instead of real math. The result is anxiety, underspending, or worse — running out of money late in life.
This article breaks down five facts that determine your retirement timeline, shows you the math tools professionals use, and gives you practical steps to extend your savings horizon.
1. Life Expectancy Sets the Baseline
How long your retirement money needs to last starts with how long you are likely to live. The Social Security Administration's Actuarial Life Table shows that a healthy 65-year-old today has a meaningful chance of living into their 90s — roughly one in three 65-year-olds will live past 90, according to SSA projections.
Planning to age 85 is a common mistake. If you retire at 65 and live to 95, a 20-year plan falls ten years short, and any estimate of how long will retirement money last must account for that possibility.
A useful rule: plan to age 95, then adjust for your health and family history. If your parents lived into their 90s, extend your planning horizon further.
How to apply this: Use the SSA Life Expectancy Calculator to get a personalized estimate, then add five years to the result as your planning target. This single step makes any calculation of how long will retirement money last far more realistic.
2. The 4% Rule Offers a Starting Benchmark
The most famous answer to how long will retirement money last comes from the 4% rule, which originated with financial planner William Bengen's 1994 research and was validated by the "Trinity Study" from Trinity University.
The finding: withdrawing 4% of your portfolio in year one of retirement, then adjusting for inflation each year, historically made money last at least 30 years across most market conditions.
Here's what that looks like in practice:
| Starting Portfolio | 4% Annual Withdrawal | Approximate Monthly Income |
|---|---|---|
| $500,000 | $20,000 | ~$1,665 |
| $1,000,000 | $40,000 | ~$3,330 |
| $2,000,000 | $80,000 | ~$6,665 |
The rule has limits. It was based on U.S. stock and bond returns from historical periods, and researchers like Bengen himself have suggested 4.5% or higher may be sustainable, while others argue for more caution given today's valuations. Either way, the 4% rule remains the standard starting point for estimating how long will retirement money last.
How to apply this: Multiply your savings by 4% to estimate a sustainable first-year withdrawal, then treat that number as a floor to test against your expected expenses.
3. Your Withdrawal Rate Beats Any Fixed Rule
A fixed percentage only tells part of the story. What actually determines how long will retirement money last is the interaction between three factors: your withdrawal rate, your asset allocation, and market sequence.
- Withdrawal rate: Higher rates drain portfolios faster, especially early in retirement.
- Asset allocation: A mix of stocks and bonds determines both growth and volatility.
- Sequence of returns: Big losses in your first few retirement years do far more damage than the same losses later.
Consider a retiree who withdraws 6% annually in a flat market: their money may last under 20 years. The same portfolio with a 3.5% withdrawal rate can stretch past 35 years. The difference isn't luck — it's the rate, and it's the single biggest lever you control over how long will retirement money last.
Vanguard's retirement research consistently shows that flexible spending — cutting withdrawals 10% in down years — dramatically improves portfolio survival rates compared to rigid withdrawals.
How to apply this: Build a "guardrail" system — set a target withdrawal rate, then reduce spending temporarily whenever your portfolio drops more than 10-15% from its starting value.
4. Healthcare Costs Are the Wildcard
Healthcare is the expense retirees most often underestimate, and it can dramatically change how long will retirement money last. Fidelity's annual Retiree Health Cost Estimate has pegged lifetime out-of-pocket healthcare costs for a 65-year-old couple at well over $300,000 in recent years — and that figure excludes long-term care.
Three cost categories matter most:
- Medicare premiums and out-of-pocket costs — rising faster than general inflation in many years.
- Dental, vision, and hearing — largely not covered by traditional Medicare.
- Long-term care — Genworth's Cost of Care surveys show assisted living and nursing home costs running tens of thousands of dollars per year, varying widely by state.
A single long-term care stay can wipe out years of careful withdrawals. This is why "money lasting 30 years" assumes no catastrophic health event.
How to apply this: Get a long-term care cost estimate for your state, then decide between self-insuring, a long-term care policy, or a hybrid life insurance/LTC product before you retire. Building this buffer into your plan is essential to knowing how long will retirement money last in a worst-case scenario.
5. Free Calculators Give You a Real Answer
You don't need to guess. Several free, reputable tools model your specific situation and show you exactly how long will retirement money last based on your own numbers:
- Fidelity Retirement Score — Fidelity's free tool estimates whether you're on track and shows how changes in spending or retirement age affect your outlook.
- Vanguard Retirement Nest Egg Calculator — models how long a portfolio survives at a given withdrawal rate and asset allocation.
- SSA benefits calculators — estimate your Social Security income, which reduces how much your savings must cover.
Run your numbers through at least two tools. If one says 22 years and another says 28, the gap tells you where your assumptions differ — usually spending estimates or investment returns.
How to apply this: This week, spend 30 minutes entering your actual balances and expenses into Fidelity's or Vanguard's calculator, then write down your projected runway.
Frequently Asked Questions About how long will retirement money last
How long will $500,000 last in retirement?
At a 4% withdrawal rate, $500,000 supports about $20,000 per year and is designed to last 30 years. If you withdraw $40,000 annually instead, the money may be exhausted in roughly 12-15 years. Add Social Security income on top, and how long will retirement money last becomes much more comfortable for a moderate spender.
What happens if I retire during a market crash?
Early losses combined with withdrawals — called sequence-of-returns risk — can cut your retirement timeline by five years or more, which is a major factor in how long will retirement money last. A practical fix is keeping one to two years of expenses in cash so you never sell stocks at depressed prices.
Some retirees also delay retirement by a year or two to let portfolios recover.
Does Social Security count when calculating how long my money will last?
Yes, and it matters enormously. Social Security replaces a larger share of income for lower earners and provides inflation-adjusted, lifetime payments that act as longevity insurance. Every projection of how long will retirement money last should subtract expected Social Security benefits from your annual expenses.
Delaying benefits from 62 to 70 increases your monthly check substantially — roughly 8% per year of delay under current SSA rules.
Should I annuitize part of my savings to make money last longer?
An income annuity converts a lump sum into guaranteed lifetime payments, removing longevity risk for that portion. The trade-off is loss of liquidity and inheritance value. A common approach is annuitizing only enough to cover essential expenses — housing, food, healthcare — and keeping the rest invested for flexibility.
For many retirees, this guarantees a baseline regardless of how long will retirement money last in portfolio form.
How do taxes affect how long will retirement money last?
Significantly. Withdrawals from traditional 401(k)s and IRAs are taxed as ordinary income, while Roth withdrawals are tax-free. A $60,000 withdrawal from a traditional IRA may deliver only ~$48,000 after tax, which shortens how long will retirement money last by 20% or more.
Planning your withdrawal order — and doing Roth conversions in low-income years — can stretch the same balance further.
Conclusion: Take Control of Your Retirement Timeline
The answer to how long will retirement money last isn't a mystery — it's math you can run yourself.
- Plan to age 95, not 85, to cover longevity risk.
- Start at a 4% withdrawal rate and build in flexibility for down markets.
- Budget for healthcare, especially long-term care, before you retire.
- Run your numbers through free tools like Fidelity's and Vanguard's calculators.
Your next step: open one retirement calculator this week, enter your real balances and expenses, and write down your projected runway. Once you know how long will retirement money last at your current pace, you can adjust spending, savings, or retirement age with confidence — not guesswork.
