What Is the 4% Rule for Retirement? Does It Still Work?

The 4% rule is a retirement withdrawal guideline stating you can withdraw 4% of your portfolio in the first year of retirement, then adjust that dollar amount for inflation each year, with a high probability of your money lasting at least 30 years. On a $1,000,000 portfolio, you would withdraw $40,000 in year one. If inflation is 3%, year two's withdrawal is $41,200. Year three: $42,436. And so on.

The rule was developed by financial planner William Bengen in 1994. He analyzed every 30-year retirement period from 1926 to 1992 and found that a 4% initial withdrawal rate, adjusted annually for inflation, survived every historical period — even those starting right before the Great Depression and the stagflation of the 1970s. A 50/50 stock-bond portfolio never ran out of money in any 30-year period at this rate.

How the 4% Rule Works in Practice

The rule works in reverse to determine how much you need saved. If you need $60,000 per year in retirement income, divide by 0.04: $60,000 / 0.04 = $1,500,000. That is your target portfolio size. For $80,000 per year, you need $2,000,000. For $100,000, $2,500,000. The simple formula: Required Portfolio = Annual Spending × 25.

Social Security and pension income reduce the amount your portfolio needs to cover. If you receive $24,000/year from Social Security and need $60,000 total, your portfolio only needs to cover $36,000, requiring $900,000 instead of $1,500,000. Any guaranteed income source acts as a powerful supplement.

The Research Behind the Rule

Bengen's original study tested withdrawal rates from 3% to 7% across every starting year from 1926 to 1992. At 4%, the portfolio survived every 30-year period. At 5%, several periods failed, particularly those starting in 1965-1969 (before the 1970s stagflation). At 3%, not a single period came close to failure — the worst case still had substantial money remaining after 30 years.

The Trinity Study (1998) expanded on Bengen's work using different stock-bond allocations. Key findings: a 50% stock / 50% bond portfolio had a 95% success rate at 4% over 30 years. A 75% stock portfolio had a 98% success rate. Portfolios heavier in stocks had higher success rates for longer time periods because stocks provide the growth needed to offset inflation and withdrawals.

Does the 4% Rule Still Work?

The 4% rule has faced scrutiny in the 2020s for several reasons. Bond yields were historically low for much of 2010-2021, reducing returns on the fixed-income portion of the portfolio. People are living longer — a 65-year-old today may need 35-40 years of retirement income, not 30. And past US stock market performance may not predict future returns as reliably.

Some financial planners now recommend a more conservative 3.3% to 3.5% withdrawal rate for early retirees or those expecting below-average market returns. Others argue that the 4% rule remains conservative enough because Bengen's original analysis used the worst historical periods. The rule survived the Great Depression, two world wars, and 1970s stagflation — it has proven remarkably resilient.

Adjustments and Alternatives

Dynamic Withdrawal Strategies

Instead of rigidly following a fixed percentage, some retirees adjust based on portfolio performance. In strong market years, you might withdraw 4.5%. After a market crash, you might cut back to 3.5%. This flexibility dramatically improves portfolio survival rates. The Guyton-Klinger guardrails approach formalizes this: if your current withdrawal rate rises above 5% of portfolio value, you cut spending; if it drops below 3%, you give yourself a raise.

The Bucket Strategy

Divide your portfolio into three buckets: Bucket 1 holds 1-2 years of expenses in cash and short-term bonds. Bucket 2 holds 3-7 years of expenses in intermediate bonds. Bucket 3 holds the rest in stocks for long-term growth. You spend from Bucket 1, refill it from Bucket 2 during normal markets, and refill Bucket 2 from Bucket 3 during strong markets. This prevents selling stocks during downturns.

Common Mistakes With the 4% Rule

• Ignoring taxes — the 4% is gross, not net. If you owe 20% tax on withdrawals from traditional accounts, you need to withdraw more to net $40,000.
• Forgetting healthcare costs — Medicare does not cover everything, and healthcare inflation typically runs higher than general inflation.
• Not accounting for Social Security timing — delaying Social Security from 62 to 70 increases monthly benefits by about 77%, significantly reducing portfolio withdrawal needs.
• Assuming constant spending — most retirees spend more in early active retirement and less in later years, which the fixed-rule framework does not capture.