The 4% Rule Under Pressure: Safe Withdrawal Rates in 2026

For many people in the FIRE community, the 4% rule is practically scripture. Retire with 25 times your annual expenses saved, withdraw 4% in year one, adjust for inflation each year, and your portfolio should last 30 years. Clean, simple, powerful.

But a growing number of researchers and financial planners are asking whether that rule holds up in the current environment. Market valuations, as measured by metrics like the cyclically adjusted price-to-earnings ratio (often called the CAPE ratio or Shiller PE), have remained elevated for an extended period. And when markets start at high valuations, historical data suggests that the returns over the following decade tend to be lower than the long-run average.

That does not mean the 4% rule is broken. It means the conversation is more nuanced than a single number implies, and for early retirees with 40 or 50-year horizons, the nuance matters enormously. This article walks through both sides of the debate, explains what the research actually says, and shows why modeling different withdrawal rates with tools like fidser's retirement calculator can give you a clearer picture of where you stand.

The 4% guideline traces back to research by financial planner William Bengen, published in 1994 in the Journal of Financial Planning. Bengen analyzed historical US stock and bond return data going back to 1926 and found that a retiree withdrawing 4% of their initial portfolio annually, adjusted for inflation each year, would have survived every 30-year retirement period in the historical record, even those starting just before major market crashes.

Subsequent research, including a widely cited analysis often called the Trinity Study, broadly supported Bengen's findings. The study looked at various stock and bond allocations and found that portfolios heavy in equities had high success rates at 4% withdrawal rates over 30-year periods.

A few important caveats that are often overlooked:

• The original research was built around a 30-year retirement horizon, not the 40 or 50-year timelines many early retirees face.
• The historical data used was US-specific. Global diversification may produce different outcomes.
• The research was backward-looking, based on returns that included some of the most productive decades in US market history.
• A 95% historical success rate still means some scenarios failed. Those failures tended to cluster around retirements that began in periods of high valuations and low subsequent returns, which is relevant context for today.

Understanding these foundations matters because it reveals where the legitimate criticism comes from, and where the 4% rule's defenders have a point too.

The core of the bearish argument against 4% today rests on valuation-based return forecasting. The CAPE ratio, developed by economist Robert Shiller, measures stock prices relative to 10-year average inflation-adjusted earnings. Historically, starting a retirement when the CAPE ratio is high has been associated with lower subsequent 10 and 15-year returns compared to starting when valuations are modest.

This matters for retirees because of a risk known as sequence of returns risk. If your portfolio delivers poor returns in the early years of retirement while you are withdrawing from it, the damage compounds in a way that later strong returns cannot fully repair. A retiree who retires into a decade of below-average returns faces a meaningfully higher chance of portfolio depletion than the historical averages suggest, simply because of timing.

Several researchers and planning firms have published analyses suggesting that, given elevated starting valuations, a more conservative starting withdrawal rate in the range of 3% to 3.5% may offer a higher probability of portfolio survival, particularly for those with longer time horizons. The logic is straightforward: if future returns are expected to be lower than historical averages, then the historical success rates associated with 4% may overstate the true probability of success going forward.

For early retirees specifically, this concern is amplified. A 45-year-old retiring today may need their portfolio to last 45 or more years. The original 4% research was never designed to stress-test a 45-year horizon, and when researchers have extended the analysis, success rates decline meaningfully at longer durations.

The 4% rule has its defenders, and their arguments deserve equal weight. A few of the most substantive counterpoints:

Valuations are an imperfect forecasting tool. While there is a historical relationship between starting valuations and subsequent returns, the relationship is not tight enough to use as a precise planning input. Markets have remained at elevated valuations for extended periods while still delivering reasonable returns. Timing retirement around valuation forecasts introduces its own risks.

Retirees are not passive. The original research modeled rigid, inflation-adjusted withdrawals with no flexibility. In practice, most retirees naturally adjust their spending. Spending less in a down market, taking on part-time work temporarily, or adjusting discretionary expenses can dramatically improve portfolio survival even at 4%. Strategies like this are sometimes called dynamic withdrawal approaches, and they can meaningfully change the math.

Other income sources change the picture. Many retirees have Social Security benefits, pension income, rental income, or part-time earnings that cover a portion of their expenses. If fixed income sources cover 50% of your spending, your portfolio withdrawal rate is effectively half of whatever the headline number suggests. The 4% rule applies to your portfolio withdrawals, not your total income.

Bengen himself has revisited his work. In subsequent research, Bengen has suggested that a wider asset class diversification, including small-cap stocks, could support starting withdrawal rates modestly above 4%. The original number was deliberately conservative.

The honest summary is that neither camp has a definitive answer. Reasonable, well-informed researchers disagree, which is itself a signal that rigid adherence to any single number carries risk.

Rather than treating the debate as something to resolve in the abstract, it is worth understanding what the different rates mean in concrete terms. Consider a hypothetical early retiree with a $1.5 million portfolio at age 50. This is illustrative only and not representative of any specific individual's situation.

• At 4%: Annual withdrawals of $60,000 in year one, indexed to inflation each year.
• At 3.5%: Annual withdrawals of $52,500 in year one. That is $7,500 less per year, or $625 per month.
• At 3%: Annual withdrawals of $45,000 in year one. That is $15,000 less per year, or $1,250 per month.

The flip side of a lower withdrawal rate is a higher required savings target to fund the same lifestyle. A household spending $60,000 per year needs $1.5 million at 4%, $1.71 million at 3.5%, and $2 million at 3%. That gap represents years of additional saving for many households, which is why the choice of rate has real consequences for when someone retires.

There is no universally correct answer in these numbers. Each rate reflects a different tradeoff between security and flexibility. A 3% rate offers a wider margin of safety but demands more from the accumulation phase or requires lower spending. A 4% rate allows an earlier retirement or a higher spending level but requires more confidence in portfolio resilience, or more willingness to adapt if markets disappoint.

This is exactly the kind of scenario where running your own numbers is far more valuable than relying on a rule of thumb. fidser's retirement calculator lets you model different starting withdrawal rates, adjust your assumed rate of return, and see how your portfolio holds up across different time horizons. Exploring the range from 3% to 4% side by side can clarify which tradeoffs feel acceptable given your own circumstances.

While no article can tell you which withdrawal rate is right for your situation, there are factors that financial planners commonly weigh when helping clients think through this decision. These are considerations worth bringing to a conversation with a qualified adviser.

• Retirement timeline: A 40 or 50-year retirement is meaningfully different from a 25 or 30-year one. Longer timelines generally warrant more conservative starting assumptions, all else being equal.
• Spending flexibility: Retirees who can reduce spending by 10-15% during a market downturn without serious hardship have a natural buffer that partially offsets the risk of a higher withdrawal rate. Those with largely fixed expenses have less room to adapt.
• Other income sources: Social Security benefits, a pension, rental income, or the possibility of part-time work can supplement portfolio withdrawals and reduce the burden placed on your invested assets. Someone planning to claim Social Security at 67 has a different picture than someone relying entirely on their portfolio for 20 years before benefits begin.
• Asset allocation: The original 4% research was modeled with significant equity exposure, typically 50-75% stocks. Very conservative allocations have historically supported lower sustainable withdrawal rates, while higher equity allocations have generally supported higher ones, though with greater short-term volatility.
• Healthcare costs: For early retirees, healthcare spending before Medicare eligibility at 65 can be a significant variable. Understanding the healthcare gap in early retirement is an important part of sizing your withdrawal needs accurately.

None of these factors produces a formula. They are inputs to a conversation, ideally one that includes a retirement income specialist or fee-only financial planner who can help you stress-test your specific plan.

This article is for general educational purposes only and does not constitute personalised financial advice. Withdrawal rate strategies involve complex variables unique to each individual's situation. Readers are strongly encouraged to consult a qualified financial adviser or retirement income specialist before making decisions about retirement withdrawals or planning assumptions.