The 4% Rule for Retirement Withdrawals: Does It Work?

The 4% rule says to withdraw 4% of your retirement portfolio in the first year, then increase the dollar withdrawal with inflation in later years rather than repeatedly taking 4% of the current balance. William Bengen’s original historical analysis found that this approach supported at least 30 years of withdrawals across the U.S. historical periods he tested when used with a diversified stock-and-bond portfolio. That does not make 4% a guaranteed safe rate today. Current research produces different starting rates depending on return assumptions, portfolio mix, retirement length, success target, and spending method. Morningstar’s 2026 retirement-income research estimates 3.9% for its base-case fixed inflation-adjusted approach, while flexible strategies can support different spending patterns. Use 4% as a planning reference, then test your own retirement horizon, taxes, fees, Social Security, portfolio allocation, and ability to reduce spending after weak markets.

Few retirement rules are quoted as often as the 4% rule because it turns a complicated question into simple arithmetic.

On a $1 million starting portfolio, 4% equals $40,000. Withdraw $40,000 in the first year, increase that dollar amount with inflation each year, and the portfolio is supposed to support a long retirement.

Simple arithmetic is part of the appeal. Its simplicity also explains why the rule is often misunderstood.

Bengen’s original research did not prove that every retiree can spend exactly 4% safely. His analysis tested a specific withdrawal method against historical U.S. market and inflation data. Change the retirement length, investments, spending pattern, fees, taxes, or future returns and the result can change too.

Key Takeaways

The 4% rule is a first-year withdrawal rule: Later withdrawals are based on the original dollar amount adjusted for inflation, not 4% of each year’s portfolio balance.
It came from historical testing: William Bengen examined U.S. stock, Treasury, and inflation history rather than guaranteeing future returns.
The original goal was portfolio longevity: Bengen used a 30-year minimum retirement horizon as a central planning threshold.
Sequence risk matters: Poor returns and high inflation early in retirement can be much more damaging than the same average returns arriving in a different order.
Current estimates can differ from 4%: Morningstar’s 2026 base-case research estimates a 3.9% starting rate for a fixed inflation-adjusted strategy under its assumptions.
Flexibility changes the math: Retirees willing to reduce spending after weak markets may be able to use different withdrawal strategies than someone requiring a fixed inflation-adjusted paycheck.
Taxes and fees are not optional: A portfolio withdrawal is not always the same as spendable income.
Your time horizon matters: A retiree planning for 40 years should not automatically use the same assumptions as someone planning for 25 or 30 years.

What the 4% Rule Actually Says

Under the classic rule, the portfolio value at the beginning of retirement establishes the first withdrawal.

First-year withdrawal = Starting retirement portfolio × 4%

Example: You retire with $800,000.

First-year withdrawal: $800,000 × 4% = $32,000.

If inflation were 3% during the first year, the second-year withdrawal under the classic approach would increase to approximately $32,960. You would not simply calculate 4% of the new portfolio balance.

The two withdrawal methods produce different spending patterns.

Withdrawing 4% of the current portfolio every year produces a different pattern. Market declines reduce the dollar withdrawal under that method, while portfolio gains increase it. That approach reduces the risk of mathematically exhausting the portfolio but creates much more variable spending.

Bengen’s approach aims for a steadier inflation-adjusted lifestyle. Portfolio assets absorb more of the market variability instead of passing all of it directly into annual spending.

Where the Rule Came From

Financial planner William Bengen published the research that became associated with the 4% rule in the Journal of Financial Planning in 1994.

Bengen tested retirement withdrawals against historical U.S. investment returns and inflation. One of the central examples used a portfolio of 50% common stocks and 50% intermediate-term Treasury securities, rebalanced over time.

His analysis used a four-part withdrawal method:

choose a percentage of the starting portfolio;
withdraw that dollar amount during the first year;
increase subsequent dollar withdrawals with inflation; and
measure how long the portfolio lasted across different historical retirement start dates.

Historical results showed that a 4% first-year withdrawal followed by inflation adjustments did not exhaust the tested 50/50 portfolio before roughly 33 years in the historical scenarios he analyzed. Bengen treated that historical result as support for a roughly 4% starting ceiling for someone seeking at least about 30 years of portfolio longevity.

Long-run averages alone did not capture the risk, a point Bengen emphasized. Retirements that begin near severe market losses and high inflation can produce very different results from those enjoying strong early returns.

The original rule was not “earn an average return above 4%, therefore 4% is safe.” Bengen’s work focused on the actual order of historical returns and inflation because bad years early in retirement can damage a withdrawal plan even when long-term averages look acceptable.

Why Sequence of Returns Can Break a Withdrawal Plan

Investment returns are not received as one smooth annual average.

Imagine two retirees who both experience the same set of returns over 20 years, but in reverse order.

Retiree A receives strong returns early and weak returns later.
Retiree B receives the weak returns immediately after retirement and stronger returns later.

Without withdrawals, the order might have a much smaller effect on the final compounded result.

During retirement, withdrawals change the outcome. Retiree B must sell assets while the portfolio is already depressed. Those shares are no longer invested when the later recovery occurs.

Illustration: A portfolio falls sharply during the first two years of retirement while the retiree continues withdrawing an inflation-adjusted dollar amount. The portfolio now has two pressures at once: market losses and withdrawals. Even if returns improve later, fewer assets remain to participate in the recovery.

Sequence-of-returns risk is one of the strongest arguments for spending methods that can adjust after market declines instead of treating the retirement paycheck as permanently fixed regardless of portfolio conditions.

Does the 4% Rule Still Work Today?

As a planning benchmark, 4% still works well. No universal current safe-withdrawal guarantee follows from it.

Modern retirement research can produce starting withdrawal rates above or below 4% because the answer changes with the assumptions.

Morningstar’s State of Retirement Income research for 2026 estimates a 3.9% starting safe withdrawal rate for its base-case approach to consistent inflation-adjusted spending. That estimate reflects Morningstar’s own capital-market assumptions, portfolio modeling, retirement horizon, and probability-of-success framework.

A 0.1-percentage-point gap between 3.9% and 4% makes an important point: the 4% rule remains in the neighborhood of serious contemporary research, but the exact decimal is not timeless.

Approach	What the number represents
Bengen historical framework	A starting withdrawal tested against historical U.S. returns and inflation, with later withdrawals adjusted for inflation
Current forward-looking research	A starting withdrawal derived from modeled future returns, inflation, portfolio mixes, retirement length, and chosen success criteria
Your retirement plan	The amount your specific spending, income, assets, taxes, timeline, and flexibility can support

Do not interpret a research estimate of 3.9% as proof that 4.0% is dangerous, or 4% as proof that 4.5% is reckless. Small changes in assumptions can move the recommended starting rate.

Withdrawal rates are outputs of a retirement plan, not laws of nature.

Your Retirement Length Can Matter More Than the Rule

Bengen’s original framework is commonly associated with a retirement of roughly 30 years.

That may fit someone retiring at 65 and planning through their mid-90s. Early retirees at 50 or 55 may find the same assumption much less comfortable.

Longer withdrawal horizons create several additional pressures:

more years of spending;
more exposure to inflation;
more opportunities for severe bear markets;
more uncertainty around health and long-term care;
fewer working years in which to rebuild savings; and
a stronger need for long-term portfolio growth.

Shorter retirements create the opposite effect. Someone beginning retirement much later, with strong Social Security or pension income and a shorter expected portfolio horizon, may not need the same withdrawal assumptions as a 55-year-old early retiree.

The withdrawal rate should follow the retirement timeline rather than the other way around.

If you are considering a long retirement, the early-retirement guide explains how health coverage, Social Security timing, and account access create additional bridge years before the traditional retirement milestones.

Portfolio Mix Changes What a Withdrawal Rate Means

Withdrawing 4% from an almost-all-cash portfolio is not economically equivalent to withdrawing 4% from a diversified stock-and-bond portfolio.

Portfolio allocation influences:

expected long-term return;
volatility;
inflation protection;
the severity of short-term losses;
how often the portfolio must be rebalanced; and
how much sequence risk the retiree can tolerate.

Bengen’s original examples showed that portfolios with too little stock exposure could struggle to generate enough long-term growth, while very high stock exposure increased vulnerability to severe market declines.

His historical work found the strongest minimum portfolio longevity in a broad zone around 50% to 75% stocks under the assumptions he tested, rather than proving that one exact allocation is optimal for every retiree.

Current research may use different capital-market assumptions and portfolio allocations.

Withdrawal rates and investment strategy cannot be designed independently. Retirees cannot safely raise the expected return in a spreadsheet, take more investment risk, and assume the higher withdrawal is now guaranteed.

More stocks do not automatically mean a higher safe withdrawal rate. Stocks can improve long-term growth but also increase short-term volatility. A severe decline near the beginning of retirement can be particularly damaging when withdrawals are already underway.

Taxes and Fees Can Make 4% Feel Like Less

A 4% withdrawal describes portfolio cash flow, not necessarily the amount available to spend after taxes and costs.

Example: A retiree with $1 million uses a 4% starting withdrawal and takes $40,000. If most of the withdrawal comes from a pre-tax Traditional IRA or 401(k), part or all of the distribution can be included in federal taxable income. The retiree does not necessarily have the full $40,000 available for household spending.

Your retirement-income plan may also include:

investment expense ratios;
advisory or management fees;
account fees;
federal income tax;
state income tax; and
tax interactions with Social Security and other income.

If the household needs $60,000 after tax from the portfolio, calculating 4% of $1.5 million and concluding that the problem is solved can understate the required gross withdrawal.

Build the withdrawal around the net retirement budget, then decide which retirement accounts to use and calculate the gross distribution required from each account.

The retirement-income guide explains how to coordinate Social Security, pensions, cash, portfolio distributions, and tax withholding into a practical monthly paycheck.

Flexible Spending Can Be More Powerful Than Finding the Perfect Percentage

Spending stability is central to the classic rule. You increase the withdrawal with inflation even when the portfolio has a bad year.

That is useful for budgeting, but many retirees do not spend with perfect rigidity.

Flexible spending can respond to markets.

For example:

reduce discretionary spending after a major decline;
skip an inflation increase after a weak year;
postpone a large vacation or vehicle purchase;
spend somewhat more after strong portfolio growth; or
set upper and lower limits on annual withdrawal changes.

Vanguard’s dynamic-spending research illustrates a method that allows withdrawals to move within a ceiling and floor rather than mechanically applying full inflation increases every year. Dynamic spending tries to balance stability with portfolio sustainability.

Withdrawal style	Main advantage	Main trade-off
Fixed dollar plus inflation	Stable purchasing-power target	Can ignore portfolio weakness
Fixed percentage of current portfolio	Withdrawal automatically falls when portfolio falls	Income can fluctuate sharply
Dynamic or guardrail approach	Allows controlled spending adjustments	Requires more annual decisions and willingness to change spending

Flexibility does not make every withdrawal rate safe. Adjustable spending gives the plan another lever when reality differs from the original assumptions.

Do Not Confuse the 4% Rule With Required Minimum Distributions

Required minimum distributions and retirement withdrawal rules solve different problems.

As a spending framework, 4% is a personal planning choice.

An RMD is a federal tax requirement that eventually requires owners of many tax-deferred retirement accounts to distribute at least a calculated amount after reaching the applicable starting age.

Your RMD may be:

less than what you need to spend;
close to your planned portfolio withdrawal; or
more than you actually need for current expenses.

Excess RMD cash does not have to be consumed simply because the distribution was required. After satisfying the distribution and paying applicable tax, money can generally be saved or reinvested in a taxable account if that fits the plan.

Likewise, using a 4% spending rule does not exempt you from RMD requirements when they apply.

RMD rules and account-withdrawal sequencing deserve separate tax analysis rather than being compressed into one withdrawal percentage.

How to Use the 4% Rule Without Treating It as a Promise

Treat the rule as the first stress test in a larger process.

Calculate the portfolio spending gap. Subtract Social Security, pensions, and other dependable income from the retirement budget.
Divide the first-year portfolio need by the portfolio balance. This shows the withdrawal rate your lifestyle is actually demanding.
Compare it with 4%. Use the rule as context rather than an approval threshold.
Test a lower starting rate. See what spending or saving changes would be required.
Test a higher-cost retirement. Add health, housing, tax, and irregular-expense uncertainty.
Extend the time horizon. Particularly important for early retirement.
Model bad early returns. Determine which expenses would be reduced if markets fall soon after retirement.
Include taxes and fees. Compare gross withdrawals with the amount actually available to spend.
Choose a spending policy. Decide whether withdrawals will be rigid, percentage-based, or adjusted within guardrails.
Review annually. Recalculate after major market moves, spending changes, or new income sources.

Example: Your portfolio is $1.2 million and the retirement budget requires $72,000 after dependable income is counted. The portfolio gap is $48,000 before tax, exactly 4% of the starting balance.

Instead of stopping there, test what happens if the gap becomes $55,000, the first two years deliver poor returns, retirement lasts 35 years, or taxes require a larger gross withdrawal. Then decide whether spending flexibility, additional cash, a later retirement date, or another income source gives the plan enough margin.

The Retirement Income Calculator can help compare different starting balances, spending levels, and retirement horizons. If much of the portfolio is in a workplace plan, the 401(k) Withdrawal Calculator can also test how long that balance may last under different withdrawal assumptions.

The 4% rule’s staying power comes from asking a useful question in a simple way. No single percentage works as a guarantee for every portfolio and every retirement.

Frequently Asked Questions (FAQs)

What is the 4% rule for retirement?

Under the classic 4% approach, you withdraw 4% of the retirement portfolio during the first year and then adjust that dollar amount for inflation in later years. By contrast, recalculating 4% of the current balance every year creates variable dollar withdrawals.

Does the 4% rule still work?

As a retirement-planning benchmark, 4% remains useful but is not guaranteed to be safe for every retiree. Retirement length, market returns, inflation, portfolio allocation, taxes, fees, spending flexibility, and other income can justify a different starting withdrawal.

What is a safe withdrawal rate in 2026?

There is no universal safe rate. Morningstar’s 2026 retirement-income research estimates 3.9% for its base-case fixed inflation-adjusted spending approach under its modeling assumptions. Other methods and assumptions can produce different rates.

Does the 4% rule include Social Security?

Portfolio withdrawals are the focus of the rule. Social Security and pensions should generally be modeled separately. Subtract dependable income from retirement spending first, then calculate how much the portfolio actually has to provide.

Does the 4% rule include taxes?

Not automatically. Gross portfolio withdrawals of 4% can produce less spendable income after federal and state taxes, particularly when money comes from pre-tax retirement accounts. Include taxes in the retirement cash-flow plan.

Is 4% too high for early retirement?

Potentially, yes. Early retirement can require the portfolio to support spending for much longer than the roughly 30-year horizon commonly associated with the classic rule. Test longer horizons and lower starting withdrawals rather than assuming the same rate applies.

Should I increase my withdrawal with inflation every year?

Classic implementation does, but you do not have to use a rigid inflation adjustment. Dynamic spending can reduce or skip increases after weak markets and permit more spending after stronger results, subject to the rules you establish.

Can I spend more than 4% if the market is doing well?

You can design a strategy that permits higher spending after strong portfolio performance, but raising spending permanently after a few good years can weaken long-term sustainability. Define a rule for increases and reductions rather than reacting to one year’s return.

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