The 4% Rule: Clearing Up Misconceptions With Bill Bengen – Financial Samurai

The 4% rule may be the most famous number in retirement planningand one of the most frequently misunderstood. It is often repeated as if it were a commandment carved into a stone tablet: retire, withdraw exactly 4% every year, and never touch the principal. That tidy summary is memorable, convenient, and mostly wrong.

Bill Bengen’s original research was not designed to predict a perfect spending rate for every retiree. It tested how much a person could have withdrawn from a diversified U.S. portfolio under difficult historical conditions without exhausting the account over a specified period. His work produced a conservative starting point, not an autopilot button. Bengen has since expanded his research and argued that many retirees may be able to start above 4%, depending on their portfolio, retirement length, inflation environment, and willingness to adjust.

What the 4% Rule Actually Says

Under the classic version, a retiree withdraws 4% of the portfolio’s starting value during the first year. In later years, the retiree increases the previous dollar withdrawal by inflation rather than recalculating 4% of the current balance. Bengen’s 1994 analysis used historical U.S. stock, Treasury-bond, and inflation data and focused on protecting a portfolio through adverse sequences of returns. His original safe figure was slightly above 4%, but the rounded number became famous.

A Simple $1 Million Example

Suppose a retiree begins with $1 million. The first withdrawal is $40,000. If inflation is 3% during the first year, the second withdrawal becomes $41,200. If inflation is 2% the next year, the third withdrawal becomes $42,024.

The account balance might be $1.1 million, $880,000, or something in between. The traditional method still bases spending on the original withdrawal plus inflation. That detail matters because withdrawing 4% of the current balance every year is a different strategy, usually called a constant-percentage withdrawal. It reduces the likelihood of completely exhausting the account, but annual income can bounce around like luggage on an airport baggage cart.

What Bill Bengen Was Trying to Solve

Bengen challenged the assumption that retirees could safely plan around average market returns. A portfolio can earn an acceptable long-term average and still fail if major losses and high inflation arrive during the first several years of retirement.

Withdrawals force the investor to sell assets while prices are depressed, leaving fewer shares available for the eventual recovery. This is known as sequence-of-returns risk, and it is especially dangerous near the beginning of retirement.

Bengen’s historical work also showed that “safer” does not automatically mean filling the portfolio with bonds and hiding under the dining table. Portfolios with too little stock often had weaker longevity because they lacked enough growth to overcome inflation and decades of withdrawals. Under the assumptions he studied, Bengen generally found a useful equity range of approximately 50% to 75%.

Seven Common Misconceptions About the 4% Rule

1. You Withdraw 4% of the Current Portfolio Every Year

No. The classic rule uses 4% of the initial balance in year one and then adjusts that dollar amount for inflation. A percentage-of-portfolio strategy is perfectly valid, but it produces a different spending path and should not be mislabeled as the original 4% rule.

2. You Must Live Only on Dividends and Interest

The rule is based on total return. Dividends, bond interest, capital gains, and principal are all parts of the same retirement engine.

Suppose a $1 million portfolio distributes $20,000 in dividends and the planned annual withdrawal is $40,000. The retiree does not receive $60,000 under the rule. The $20,000 of dividends is included within the $40,000 total withdrawal. The remaining $20,000 may come from interest, cash, or asset sales.

3. Four Percent Is Guaranteed to Work

Nothing involving markets, inflation, taxes, health, and human longevity comes with a cosmic warranty card. The original research asked what survived historical U.S. conditions under particular asset allocations and time horizons.

Future returns can differ from the historical record. Retirees can live longer than expected. Investment fees, taxes, healthcare costs, home repairs, and family emergencies can also place pressure on a portfolio. The rule increases the probability of success under certain assumptions; it does not guarantee success.

4. The Rule Ignores Inflation

Inflation is central to the method. The annual withdrawal rises with the cost of living, which protects purchasing power but also increases pressure on the portfolio during inflationary periods.

This is one reason the late 1960s and 1970s were so difficult in historical retirement simulations. Falling markets are unpleasant. High inflation is unpleasant. Experiencing both while withdrawing money is the financial equivalent of discovering that your umbrella has holes during a thunderstorm.

5. The Rule Was Designed for Every Retirement Length

The most familiar version assumes a retirement lasting approximately 30 years. A person retiring at 45 may need the portfolio to support 45, 50, or even 60 years. Someone retiring at 75 with substantial guaranteed income may reasonably use a shorter planning horizon.

Bengen’s later research suggests that a long retirement does not necessarily require dropping the starting rate all the way to 3%. In conversations reported by Financial Samurai, he discussed a rate around 4.3% for a horizon beyond 50 years. However, that estimate depends on his portfolio and historical assumptions. It should not be treated as a universal promise for every early retiree.

6. Lower Withdrawals Are Always Better

Lower spending generally improves portfolio survival, but retirement planning is not a contest to die with the largest brokerage statement. Excessive caution can create a different type of failure: postponing meaningful travel, generosity, hobbies, and family experiences until health or energy has disappeared.

Bengen’s newer message is partly about balancing ruin risk with regret risk. Saving enough matters, but so does using the money for the life it was intended to support.

7. One Number Should Govern the Entire Retirement

Real spending is uneven. A new retiree may travel more during the active “go-go” years, spend less during quieter middle years, and encounter higher medical or care expenses later.

A rigid inflation increase every January may be easy to model, but it is rarely how households actually behave. Dynamic spending strategies use floors, ceilings, or guardrails to adjust withdrawals when portfolio performance or personal circumstances change.

Why Bengen Now Discusses Rates Above 4%

Bengen’s research did not stop in 1994. As he expanded the number of asset classes and historical scenarios in his analysis, he raised his worst-case starting rate. His later work has commonly been associated with a 4.7% baseline, while interviews surrounding his 2025 book have discussed starting rates above 5% under certain conditions.

Financial Samurai’s conversations with Bengen explored a 5% safe withdrawal rate for a 30-year retirement. Other interviews have discussed rates around 5.25% or higher for particular market environments and portfolio structures.

These numbers are not random acts of optimism. They reflect different datasets, asset allocations, inflation conditions, market valuations, and definitions of success.

Bengen has described 4.7% as an ultraconservative historical worst-case figure under his expanded framework. Across hundreds of historical retirement starting dates, the sustainable rate was materially higher, with an average close to 7% in the research discussed by Financial Samurai and other publications.

The takeaway is not that everyone should immediately withdraw 7%. The average outcome is not the worst outcome, and a person does not know in advance which market sequence retirement will deliver. The important lesson is that a worst-case rate should not be mistaken for the expected rate.

How Can Morningstar Say 3.9% While Bengen Says 4.7% or More?

Both estimates can be reasonable because they answer different questions.

Bengen’s method is primarily historical: What starting withdrawal would have survived the difficult U.S. periods in the dataset under his portfolio and rebalancing rules?

Morningstar’s framework is forward-looking: What rate offers a specified probability of success using projected returns, inflation, current valuations, bond yields, and a chosen retirement horizon?

Morningstar’s 2025 retirement-income research estimated a 3.9% starting rate for steady, inflation-adjusted spending with a 90% probability of funds remaining after a 30-year period. The same research found that retirees willing to tolerate fluctuations in spending could begin near 6% under some flexible withdrawal systems.

That is not a contradiction. Flexibility has economic value. Cutting or freezing discretionary spending after poor returns reduces the need to sell depressed investments. Accepting less predictable income may therefore support a higher initial withdrawal.

A Practical Way to Use the 4% Rule

Start With Spending, Not a Percentage

Estimate annual essential expenses, flexible lifestyle spending, taxes, healthcare, and irregular costs such as vehicles, home repairs, weddings, and family support. Then subtract reliable income from Social Security, pensions, rental property, or annuities.

The remaining gap is the amount the investment portfolio must provide. This is more useful than multiplying every financial account by 4% and hoping the resulting number resembles your life.

Match the Rate to the Retirement Horizon

A 65-year-old planning for 30 years is solving a different problem from a 45-year-old planning for 50 years. Life-expectancy averages are useful, but couples should consider the possibility that one spouse lives well beyond the average.

Retirement length is a range of possibilities, not an expiration date stamped on a carton.

Use a Diversified Total-Return Portfolio

A retirement portfolio needs enough growth to fight inflation and enough high-quality bonds or cash to reduce forced stock sales during a downturn. The ideal allocation depends on risk tolerance, guaranteed income, spending flexibility, and the importance of leaving an inheritance.

Regular rebalancing helps keep the selected allocation from drifting after major market movements.

Create Spending Guardrails

A practical policy might skip the annual inflation increase after a negative portfolio year. It could trim travel or entertainment when the current withdrawal rate rises above a chosen ceiling and permit modest spending increases following strong performance.

Guardrails do not eliminate risk, but they give retirees a steering wheel instead of asking a spreadsheet to drive.

Account for Taxes and Account Rules

A 4% portfolio distribution is not necessarily 4% available for spending. Traditional IRA and 401(k) withdrawals may be taxable, while investment-management expenses reduce net returns.

Required minimum distributions can also exceed the amount suggested by a personal withdrawal policy. Under current federal rules, many traditional retirement-account owners generally begin RMDs at age 73, although the exact treatment depends on the account type, employment status, birth year, and other circumstances.

Does a 5% Rate Mean You Can Retire Earlier?

Mathematically, a 4% target requires savings equal to 25 times annual portfolio-supported spending. A 5% target requires 20 times spending.

If the portfolio must provide $80,000 annually, the targets are $2 million at 4% and $1.6 million at 5%. That is a substantial $400,000 difference.

However, it does not automatically mean a person can retire exactly 20% earlier. Savings compound unevenly, incomes change, markets do not follow appointment calendars, and early retirees must plan for health insurance, taxes, and access to retirement accounts before age 59½.

An Early-Retirement Example

Daniel retires at 50 with $1.5 million and wants $67,500 from investments, representing a 4.5% starting rate. Because his horizon is long, he separates $20,000 of optional travel spending, keeps a cash-and-bond reserve, skips inflation increases after negative years, and reviews the plan annually.

Flexibility does not make 4.5% risk-free, but it is sturdier than an unbreakable promise to withdraw $67,500 plus inflation regardless of market performance.

Practical Experiences: What People Often Learn After Using the Rule

The following field notes are composite scenarios based on common retirement-planning behavior. They are not claims about one identifiable household. They illustrate why the emotional side of withdrawing money can matter almost as much as the mathematics.

The Diligent Saver Who Cannot Switch From Saving to Spending

One common retiree reaches financial independence with a portfolio comfortably above the original target, then continues behaving as though every restaurant meal threatens bankruptcy. During the accumulation years, frugality created security. In retirement, the same habit can become a cage.

A written withdrawal policy helps because it turns spending into a planned action rather than a moral failure. The retiree might create a yearly “use-it-or-gift-it” travel budget, knowing that essential costs are already protected by conservative assumptions.

The lesson is that a safe withdrawal rate is not only a limit. It can also be permission. When the plan survives reasonable stress tests, enjoying some of the money is part of the job description.

The Unlucky Retiree Who Meets a Bear Market Immediately

Another retiree leaves work just before a major market decline. The long-term return forecast may still look acceptable, but the first account statement feels as though a raccoon has entered the kitchen.

A retiree who has separated essential expenses from discretionary spending can respond calmly: use part of the cash reserve, postpone a vehicle upgrade, skip the inflation increase, and rebalance according to policy rather than panic.

The key experience is that flexibility feels easiest in theory and hardest when headlines are frightening. Decisions made before the downturn are usually better than decisions improvised during it.

The Retiree Whose Spending Falls Naturally

Many households assume expenses will rise with inflation forever. In practice, spending may decline after the first decade as travel slows, mortgages end, or expensive hobbies lose their sparkle.

That does not mean late-life healthcare costs are harmless. It means retirement spending rarely follows a perfectly straight line. A plan that reviews actual expenses every year may reveal that the portfolio can support more early enjoyment than the original spreadsheet suggested.

The lesson is to measure personal inflation. National inflation data matters, but your own mixture of housing, transportation, insurance, food, travel, and medical costs determines the spending increase your lifestyle actually needs.

The Household That Forgets Taxes

A couple may calculate that a $50,000 withdrawal covers a $50,000 spending gap, only to discover that most of the money must come from a pretax IRA. The gross distribution must be larger to produce the desired after-tax cash.

Later, required minimum distributions may create additional taxable income even when the household does not need the entire distribution for living expenses.

The practical fix is to coordinate withdrawal rates with tax planning. Roth conversions, taxable-account sales, charitable gifts, and Social Security timing can affect how much of every distributed dollar reaches the checking account. The 4% rule is a portfolio-spending framework, not a tax strategy wearing a fake mustache.

The Retiree Who Discovers That Success Needs a Definition

In retirement research, success often means completing the planned period without exhausting the account. In real life, a retiree may want to preserve a home, leave an inheritance, support children, fund long-term care, or avoid watching the balance approach zero.

Another retiree may prefer to spend more aggressively and leave relatively little behind. Neither goal is automatically superior.

The most useful discovery is that withdrawal-rate debates cannot be settled until the retiree defines the destination. A plan designed to maximize lifetime spending will look different from one designed to preserve inflation-adjusted principal. The percentage comes after the purpose.

Conclusion: Use the 4% Rule as a Compass, Not Handcuffs

Bill Bengen’s work remains valuable because it transformed retirement spending from guesswork into a disciplined study of actual market sequences and inflation. The headline number, however, has overshadowed the method.

Four percent is an initial inflation-adjusted withdrawal guideline tied to particular assumptions. It is not a fixed percentage of the current balance, a requirement to live only on dividends, or a guarantee against every possible future.

Bengen’s later research suggests that diversified retirees may be able to begin around 4.7% or, under some conditions, above 5%. Forward-looking research can produce lower base rates, while flexible spending strategies can support higher ones. All may be intellectually honest because their assumptions and definitions of success differ.

The best retirement withdrawal strategy is therefore a written policy: define essential and optional spending, select a realistic horizon, diversify, manage sequence risk, account for taxes, establish guardrails, and review the plan annually.

The goal is not to worship 4%, 4.7%, or 5%. The goal is to use money without allowing either fear or overconfidence to run the household.

Note: This article is for educational purposes and does not provide individualized investment, tax, or legal advice. Retirement decisions should reflect personal expenses, assets, risk tolerance, health, tax situation, and professional guidance where appropriate.