3% vs 4% withdrawal rate: how your FIRE target changes
A withdrawal assumption connects annual spending with a target portfolio. A smaller percentage increases the target, but a larger number alone does not establish that your retirement is funded.
What does a withdrawal rate mean here?
The initial withdrawal rate is first-year annual retirement spending divided by the portfolio at retirement. Rearranging gives target = annual expenses ÷ withdrawal rate. At 4%, that is 25 times annual expenses; at 3.5%, about 28.57 times; at 3%, about 33.33 times.
Compare the same lifestyle at three rates
Example in USD: age 30 targeting 50, monthly expenses of $4,000 today and $100,000 already invested. Assume 3% expense inflation, a 7% nominal annual return divided by 12 for monthly growth, and 5% annual contribution increases. Monthly expenses at age 50 are approximately $7,224. Only the withdrawal assumption changes below.
| Withdrawal rate | Expense multiple | Target at age 50 | Required starting investment | Try it |
|---|---|---|---|---|
| 3% | 33.33× | $2,889,778 | $3,227/mo | Try 3% → |
| 3.5% | 28.57× | $2,476,953 | $2,691/mo | Try 3.5% → |
| 4% | 25.00× | $2,167,333 | $2,289/mo | Try 4% → |
The required contribution arrives at month end and increases by 5% after every 12 months. These example percentages are not recommendations or validated safe rates for a country.
Why does 3% require more than 4%?
For identical expenses, dividing by 0.03 instead of 0.04 makes the target one-third larger. This is arithmetic, not evidence that either rate is sustainable. A withdrawal assumption is also different from a portfolio return assumption.
Is any one rate safe everywhere?
No model can guarantee that. The basic withdrawal-rate shortcut does not model taxes, fees, changing returns or retirement cash flows. The optional Monte Carlo simulation explores changing returns and withdrawals over a selected horizon. Countries differ in taxes, pensions, healthcare costs and access to accounts. Country selection does not automatically account for these rules.
Two portfolios with similar average returns can experience different outcomes when money is withdrawn during losses. This sequence-of-returns risk needs retirement cash-flow analysis beyond a constant-return accumulation model.
Use the comparison carefully
Estimate recurring spending in one currency, keep today’s and future money separate, then change one assumption at a time. Compare both the target and required contribution. See the FIRE-number guide, retirement-age examples and methodology.
Explore a range of retirement outcomes
The worked examples above use fixed returns. The optional Monte Carlo simulation explores varying returns, portfolio withdrawals and percentile outcomes. Try your own assumptions →