For 30 years, "save 25 times your annual expenses and withdraw 4% a year" was the closest thing personal finance had to a settled answer. In 2026, that consensus has split. Morningstar's latest research puts the safe withdrawal rate at just 3.9%, while Bill Bengen — the analyst who invented the 4% rule back in 1994 — now says retirees can safely start as high as 4.7%. That gap sounds small until you put real money behind it: on a $1 million portfolio, it's the difference between $39,000 and $47,000 of spending a year. This guide breaks down where the 4% rule came from, why the experts disagree in 2026, and exactly how to calculate your own number.

Where the 4% Rule Came From

Financial planner Bill Bengen introduced the rule in a 1994 paper. He tested historical U.S. stock and bond returns going back to 1926 and found that a retiree who withdrew 4% of their portfolio in year one, then adjusted that dollar amount for inflation every year after, never ran out of money over any 30-year period in U.S. history — even someone unlucky enough to retire right before a major crash.

The math behind the "25x" shortcut is simple: if 4% of your portfolio covers one year of expenses, then your full portfolio needs to be 25 times your annual spending (since 1 ÷ 0.04 = 25).

Example: If you spend $60,000 a year in retirement, the classic 4% rule says you'd need a $1.5 million portfolio (60,000 × 25) to sustain that spending for 30 years.

Why 2026 Broke the Consensus

Two of the most-cited names in retirement research looked at the same question this year and landed in different places:

Source2026 Safe Withdrawal RateOn a $1M Portfolio
Morningstar (fixed spending)3.9%$39,000/year
Morningstar (flexible "guardrails")Up to 5.7%Up to $57,000/year
Bill Bengen (worst-case floor, 2025 revision)4.7%$47,000/year
Bill Bengen (flexible strategy)5.25%–5.5%$52,500–$55,000/year

Morningstar's 3.9% figure comes from its December 2025 "State of Retirement Income" report. It's up slightly from 3.7% in 2025, thanks to improved return assumptions, and applies to a retiree with a 30-year horizon holding a relatively conservative 30–50% in stocks, with the rest in bonds and cash. It's a forward-looking estimate built on projected future returns — not a look backward at history.

Bengen's 4.7% figure, published in his 2025 book A Richer Retirement, comes from expanding his original test portfolio to include small-cap stocks and international equities, which historically improved diversification and returns. He describes 4.7% as a worst-case floor, not an average — meaning most retirees in most years could safely spend more.

Key insight: Morningstar and Bengen aren't really disagreeing about the same thing. Morningstar is modeling a cautious, forward-looking baseline for a conservative portfolio. Bengen is stress-testing a stock-heavy portfolio against the worst 30-year stretch in U.S. market history. Your right number depends on which portfolio — and which risk tolerance — is actually yours.

Step-by-Step: Calculate Your Own Retirement Number

Step 1 — Estimate Your Annual Retirement Spending

Start with your current annual spending and adjust for retirement — you may spend less on commuting and work clothes, but more on healthcare and travel. Many retirees land close to 70–80% of their pre-retirement income.

Step 2 — Subtract Guaranteed Income

Social Security and any pension income reduce how much your portfolio needs to cover. The 2026 Social Security cost-of-living adjustment (COLA) is 2.8%, bringing the average retired worker's monthly benefit to roughly $2,071, or about $24,850/year.

Example: If you need $70,000/year in retirement and expect $30,000/year from Social Security, your portfolio only needs to supply the remaining $40,000/year — not the full $70,000.

Step 3 — Apply a Withdrawal Rate to Find Your Target

Divide your portfolio-funded spending gap by your chosen withdrawal rate to find your target portfolio size:

Annual Portfolio NeedAt 3.9% (Morningstar)At 4% (Classic Rule)At 4.7% (Bengen)
$30,000$769,000$750,000$638,000
$40,000$1,026,000$1,000,000$851,000
$50,000$1,282,000$1,250,000$1,064,000
$60,000$1,538,000$1,500,000$1,277,000
$80,000$2,051,000$2,000,000$1,702,000

Figures rounded to the nearest thousand; calculated as annual need ÷ withdrawal rate.

Why the Withdrawal Rate Debate Matters More in 2026

A few real economic shifts explain why 2026 estimates moved:

The 4% rule was never a recommendation. Bengen designed it as a survivable floor for the worst 30-year period in U.S. market history — not a target to aim for every year. Treating a worst-case number as your everyday spending plan can mean leaving money — and quality of life — on the table.

Fixed vs. Flexible Withdrawal Strategies

The biggest lever in the 2026 research isn't which expert you follow — it's whether your spending is fixed or flexible:

Delaying Social Security is another lever worth considering: relying on portfolio withdrawals or part-time work in your early retirement years so you can claim Social Security later generally increases lifetime guaranteed income and reduces pressure on your portfolio.

Try Our Free Retirement Calculator

Plug in your savings, expected Social Security, and withdrawal rate to see exactly how long your money will last.

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How Much Do You Actually Need? A Realistic Range

Given the 2026 data, most retirees are better served picking a range rather than a single magic number:

Key Takeaways

Sources & Disclaimer

Data referenced: Morningstar "State of Retirement Income" report (December 2025); Bill Bengen, A Richer Retirement (2025); U.S. Social Security Administration 2026 COLA announcement (October 2025); U.S. Bureau of Labor Statistics CPI data (June 2026, released July 14, 2026).

This article is for informational purposes only and does not constitute financial or retirement advice. Withdrawal rate research changes as market conditions evolve. Always consult a licensed financial advisor to build a retirement plan suited to your specific situation.