Safe Withdrawal Rate
Quick Definition
The safe withdrawal rate is the highest percentage of your retirement portfolio that you can withdraw in the first year, then adjust for inflation each subsequent year, with a high probability of your money lasting for the entire retirement period. The most widely cited figure is 4 percent, based on Bill Bengen's 1994 research and the 1998 Trinity Study, though Bengen himself updated the number to 4.7 percent in 2025.
What It Means
The safe withdrawal rate answers the most important question in retirement: how much can I spend without going broke? Get this number right and you enjoy decades of financial security. Get it wrong and you face the nightmare of running out of money in your 70s or 80s with no way to earn it back.
The concept originated with financial advisor Bill Bengen, who published a paper in the October 1994 issue of the Journal of Financial Planning. He tested every 30-year retirement period from 1926 onward using historical stock and bond returns. He found that a 4.15 percent initial withdrawal rate, adjusted for inflation each year, never depleted a portfolio in any 30-year period. He rounded down to 4 percent for safety, and the "4 percent rule" was born.
In 2025, Bengen published a book called "A Richer Retirement" that updated his research. He expanded from a simple 50/50 stock and bond portfolio to a diversified mix of 55 percent stocks, 40 percent bonds, and 5 percent cash across seven asset classes. With broader diversification and strong recent stock returns, he raised the safe withdrawal rate to 4.7 percent. In an April 2026 interview, Bengen went further, saying that based on current market conditions he considers 5.5 percent a realistic starting point, though he would not use 4.7 percent as a floor for planning.
The 1998 Trinity Study, conducted by three professors at Trinity University, confirmed Bengen's findings using a broader range of asset allocations and time periods. They found that a 50/50 stock and bond portfolio withdrawing 4 percent, adjusted for inflation, survived 95 percent or more of all 30-year historical periods. At a 5 percent withdrawal rate, survival dropped to about 82 percent. At 6 percent, it fell below 70 percent.
The safe withdrawal rate matters because it directly determines your retirement number. If your safe withdrawal rate is 4 percent, you need 25 times your annual expenses saved (1 divided by 0.04). If it is 4.7 percent, you need about 21 times your expenses. That difference of 4 years of expenses can mean working several fewer years.
How It Works
The Basic Mechanics
- Calculate your total retirement portfolio value on the day you retire
- Withdraw a percentage of that starting balance in year one
- In each subsequent year, withdraw the same dollar amount adjusted for inflation
- The percentage is based on your starting balance, not your current balance
For example, with a $1 million portfolio and a 4 percent safe withdrawal rate:
| Year | Inflation | Withdrawal | Starting Balance | Portfolio Return |
|---|---|---|---|---|
| 1 | 0% | $40,000 | $1,000,000 | 7% |
| 2 | 3% | $41,200 | $1,027,000 | -10% |
| 3 | 3% | $42,436 | $881,300 | 8% |
| 4 | 2.5% | $43,497 | $909,808 | 6% |
The withdrawal amount goes up with inflation regardless of what the portfolio does. This is what makes the safe withdrawal rate challenging: you keep spending the same inflation-adjusted amount even in years when the portfolio loses value.
Why 4 Percent and Not Higher
The 4 percent figure is conservative because it had to survive the worst historical retirement periods. The most dangerous period was 1968 to 1969, when retirees faced a combination of steep stock market declines in the early 1970s and persistently high inflation throughout the decade. A portfolio withdrawing 4 percent starting in 1968 barely survived. At 5 percent, it failed.
This danger is called sequence of returns risk. If you get bad market returns in the first few years of retirement while also withdrawing money, the portfolio can be permanently damaged. The same average return over 30 years can produce very different outcomes depending on the order of good and bad years.
Factors That Affect Your Safe Rate
Several variables change what withdrawal rate is actually safe for you:
| Factor | Effect on Safe Rate |
|---|---|
| Longer retirement (40+ years) | Lower (3.5 percent or less) |
| Higher stock allocation | Higher (up to a point) |
| Higher bond allocation | Lower (bonds return less) |
| Flexible spending (cut in down years) | Higher |
| Later Social Security claiming | Higher (more guaranteed income) |
| High inflation environment | Lower |
| Lower starting valuations | Higher |
Bengen's Updated 4.7 Percent
Bengen's 2025 update to 4.7 percent came from two changes. First, he diversified the portfolio beyond large-cap stocks and intermediate bonds. His new mix includes 55 percent stocks (split across large-cap, small-cap, and international), 40 percent bonds (intermediate and long-term), and 5 percent cash. Second, stock returns in recent decades have been above the long-term average, which gives retirees more cushion.
On a $1 million portfolio, the difference between 4 percent and 4.7 percent is $7,000 per year in spending. Over a 30-year retirement, that is $210,000 in additional spending power, not counting inflation adjustments. However, Bengen cautions that 4.7 percent assumes a well-diversified portfolio and a 30-year horizon. For longer retirements, he recommends sticking closer to 4 percent.
Variable Withdrawal Strategies
Instead of the fixed inflation-adjusted approach, many planners now recommend variable strategies that adjust spending based on portfolio performance:
- Guardrails approach: Start at 4 to 5 percent. If the withdrawal rate rises above 6 percent of the current portfolio value (because the portfolio shrank), cut spending by 10 percent. If it falls below 3 percent (because the portfolio grew), increase spending.
- Percentage of portfolio: Withdraw a fixed percentage of the current balance each year. Income fluctuates but the portfolio can never run out.
- Bucket strategy: Keep 2 to 3 years of expenses in cash, 5 to 7 years in bonds, and the rest in stocks. Withdraw from cash, refill from bonds and stocks as they recover.
Read our guide on the bucket strategy for retirement income for a detailed implementation.
Real-World Examples
Example 1: The 4 Percent Baseline
Robert retires at 65 with $1.2 million. He withdraws 4 percent, or $48,000, in year one. He adjusts for inflation each year. His portfolio is 60 percent stocks and 40 percent bonds. Based on historical data, this portfolio has a 95 percent probability of lasting 30 years, taking him to age 95.
| Year | Withdrawal | Portfolio Start | Return | Portfolio End |
|---|---|---|---|---|
| 1 | $48,000 | $1,200,000 | 6% | $1,224,000 |
| 2 | $49,440 | $1,224,000 | -8% | $1,076,640 |
| 3 | $50,923 | $1,076,640 | 10% | $1,133,180 |
| 10 | $59,700 | $1,180,000 | 7% | $1,203,010 |
| 20 | $80,500 | $1,450,000 | 5% | $1,442,250 |
| 30 | $108,800 | $980,000 | 6% | $930,192 |
Example 2: The Early Retiree's Dilemma
Lisa retires at 50 with $1.5 million. She wants to withdraw $60,000 per year (4 percent). But her retirement could last 45 years, not 30. The 4 percent rule was tested for 30-year periods. For a 45-year horizon, the safe withdrawal rate drops to about 3.5 percent, or $52,500 per year. If she insists on $60,000, her probability of success falls to about 80 percent based on historical data. She should either save more, spend less, or plan to earn some income in the early years. Read about the FIRE movement for strategies on handling longer retirement horizons.
Example 3: The 4.7 Percent Optimist
Mark and Susan retire at 67 with $900,000. They use Bengen's updated 4.7 percent rate, withdrawing $42,300 in year one. Their portfolio is diversified across seven asset classes as Bengen recommends. They also delay Social Security to 70, which adds $8,000 per year in guaranteed income. The combination of a slightly higher withdrawal rate and higher Social Security gives them a comfortable lifestyle. But they monitor their portfolio and agree to cut spending if the balance drops below $700,000.
Key Points to Remember
- The traditional safe withdrawal rate is 4 percent, based on Bengen's 1994 research and the 1998 Trinity Study. This means you need 25 times your annual expenses.
- Bill Bengen updated his figure to 4.7 percent in 2025 using a more diversified portfolio. In 2026, he suggested 5.5 percent may be realistic based on current conditions, though he does not recommend using it as a planning floor.
- The safe withdrawal rate assumes you adjust your withdrawal for inflation every year, regardless of portfolio performance.
- Longer retirements require lower withdrawal rates. For a 40-year retirement, use 3.5 percent. For 50 years, use 3 percent.
- Sequence of returns risk is the biggest threat. Bad returns in the first few years of retirement can permanently damage the portfolio.
- Variable withdrawal strategies (guardrails, percentage of portfolio, bucket strategy) can improve outcomes by adjusting spending to market conditions.
Common Mistakes to Avoid
- Using the safe withdrawal rate as a guarantee: It is a probability, not a promise. The 4 percent rule had a 95 percent success rate historically, which means it failed 5 percent of the time. Plan for the possibility of needing to cut spending.
- Withdrawing a fixed percentage of the current balance each year: This is a different strategy than the safe withdrawal rate. The safe withdrawal rate is based on your starting balance, adjusted for inflation. Withdrawing 4 percent of the current balance means your income drops in down years, which is actually safer but produces volatile income.
- Ignoring valuation at retirement: If you retire when stocks are expensive (high P/E ratios), your safe withdrawal rate is likely lower. The S&P 500 trailing P/E was about 27 in August 2026, well above the historical average of about 16. Starting retirement at high valuations historically led to lower safe withdrawal rates.
- Not accounting for taxes: If your money is in a traditional 401(k) or IRA, every withdrawal is taxed as ordinary income. A 4 percent withdrawal from a $1 million traditional IRA in the 22 percent bracket nets only $31,200 after federal taxes. Use our tax bracket calculator to estimate the impact.
- Forgetting about inflation: A $40,000 withdrawal today will need to be about $81,000 in 25 years at 2.5 percent inflation. The safe withdrawal rate accounts for this, but many people underestimate how much their spending will increase.
- Using 4 percent for a 40-year retirement: The original research tested 30-year periods. If you retire at 55 and live to 95, you need a 40-year horizon. Use 3.5 percent or lower for retirements longer than 30 years.
Related Concepts
The safe withdrawal rate sits at the center of retirement planning. It determines your retirement number and connects directly to your withdrawal rate, which is the actual percentage you withdraw each year. The biggest risk to a withdrawal strategy is sequence of returns risk, which is the danger of bad market returns early in retirement. Your asset allocation between stocks and bonds affects how much you can safely withdraw. Inflation erodes purchasing power over time, which is why withdrawals must be adjusted upward each year. The FIRE movement relies on the safe withdrawal rate to calculate financial independence targets. Use our retirement number calculator and retirement calculator to apply these concepts to your own situation. Read our guides on the 4 percent rule and safe withdrawal rate, how much cash to keep in retirement, the bucket strategy, and sequence of returns risk.
Frequently Asked Questions
Q: Is the 4 percent rule still valid in 2026? A: The 4 percent rule remains a conservative planning baseline. Bill Bengen, who created it, updated his figure to 4.7 percent in 2025 using a more diversified portfolio. In 2026, he suggested 5.5 percent may be realistic given current market conditions. However, with the S&P 500 trading at elevated valuations (trailing P/E around 27 in August 2026), many planners still recommend 4 percent or lower for safety.
Q: What withdrawal rate should I use for a 40-year retirement? A: For retirements longer than 30 years, reduce your withdrawal rate. Historical testing suggests 3.5 percent for a 40-year horizon and 3 percent for a 50-year horizon. Early retirees should use these lower rates or adopt a variable withdrawal strategy that adjusts spending to portfolio performance.
Q: Does the safe withdrawal rate work with a 100 percent stock portfolio? A: A higher stock allocation historically supported higher withdrawal rates over long periods, but with much greater volatility. The worst-case scenarios in Bengen's research assumed at least some bond allocation. A 100 percent stock portfolio risks large drawdowns that can be devastating if they occur early in retirement. Most planners recommend 50 to 75 percent stocks for retirees.
Q: How does Social Security affect my safe withdrawal rate? A: Social Security reduces the amount you need to withdraw from your portfolio. If you need $60,000 per year and Social Security pays $25,000, your portfolio only needs to cover $35,000. On a $875,000 portfolio, that is a 4 percent withdrawal rate. Delaying Social Security to age 70 increases your benefit by about 8 percent per year, which reduces the burden on your portfolio. Use our Social Security estimator to model your benefit.
Q: Where can I read the original research on the safe withdrawal rate? A: Bengen's 1994 paper was published in the Journal of Financial Planning. The Trinity Study was published by Cooley, Hubbard, and Walz in 1998. Bengen's 2025 book "A Richer Retirement" contains his updated research. The SEC's investor resources provide additional guidance on retirement withdrawal strategies.
