The 4% Withdrawal Rule
Spend 4% of your portfolio annually for a high probability of never running out
The 4% Withdrawal Rule serves as the bridge between wealth accumulation and financial independence. The rule states that once your investment portfolio reaches a level where 4% of its value equals your annual living expenses, you are financially independent. You can withdraw 4% per year, adjusted for inflation, with a historically high probability of never exhausting your portfolio over a 30+ year retirement.
Collins uses this rule as both a planning target and a spending guide. If you need $40,000 per year to live, you need $1,000,000 in investments ($1,000,000 x 4% = $40,000). If you can live on $20,000, you only need $500,000. The rule reveals a powerful truth: reducing your expenses has a double effect on your path to financial independence. It both reduces the target you need to hit and increases the amount you can save to get there.
The rule originates from the Trinity Study, which analyzed historical market data and found that a 4% initial withdrawal rate, adjusted annually for inflation, from a portfolio of 50-75% stocks and 25-50% bonds had a very high success rate over 30-year periods. Collins notes that the 4% figure is conservative and that flexibility in spending during down years further increases the odds of portfolio survival.
- When 4% of your investments covers your annual expenses, you are financially independent
- Reducing expenses has a double effect: lower target and higher savings rate
- A portfolio of 50-75% stocks and 25-50% bonds historically supports a 4% withdrawal rate
- Flexibility in spending during down years dramatically increases portfolio survival odds
- The 4% rule is conservative; many retirees can safely spend somewhat more
- The rule works because stock market returns historically exceed 4% plus inflation
- Your withdrawal rate and your savings rate are the two most powerful numbers in your financial life
- Calculate your annual living expensesDetermine how much you actually spend per year. Be thorough and honest. Include housing, food, transportation, insurance, healthcare, entertainment, and all other categories. This is your withdrawal target.
- Multiply by 25 to find your financial independence numberYour annual expenses times 25 equals the portfolio size needed for financial independence at a 4% withdrawal rate. If you spend $40,000 per year, you need $1,000,000. If you spend $25,000, you need $625,000. If you spend $100,000, you need $2,500,000.
- Track your progress toward the targetMonitor the gap between your current portfolio value and your financial independence number. As your portfolio grows through contributions and compounding, and as you reduce spending, the gap closes from both directions.
- Implement flexible withdrawal in retirementOnce retired, withdraw 4% of your portfolio's initial value, adjusted for inflation each year. During years when the market drops significantly, reduce discretionary spending. This flexibility dramatically improves the long-term sustainability of your portfolio.
Collins illustrates that a person earning $25,000 per year who lives on $12,500 and invests the other $12,500 annually in VTSAX at a historical 11.9% return would reach financial independence ($312,500 at 4% = $12,500) in approximately 11.5 years. If they then stop saving and spend their full $25,000 income for 10 years while leaving the nest egg untouched, it grows to $961,946, yielding $38,478 at 4%.
The 4% rule was developed from the Trinity Study conducted by three professors at Trinity University in the 1990s. Collins adopted it as a key planning tool because it provides a simple, historically validated answer to the question every aspiring retiree asks: how much is enough? He emphasizes that the rule should be used as a guideline rather than an absolute, and that flexibility in spending provides additional safety margin.