4% Rule — What is it? Safe withdrawal rule in FIRE

Definition

The 4% rule (4% rule or safe withdrawal rate) is a financial rule stating that you can withdraw 4% of the initial portfolio value (adjusted for inflation) annually without risk of depleting funds for at least 30 years.

Where does the 4% rule come from?

The rule was formulated by William Bengen in 1994 based on analysis of historical U.S. market data (1926–1992). Later confirmed by the "Trinity Study" — research by Trinity University professors.

Bengen studied the worst possible times to start withdrawals (e.g., just before a crash) and found that 4% annually was safe in every 30-year period.

How to apply the 4% rule?

Calculating FIRE goal

FIRE Goal = Annual expenses × 25

In practice

1. Accumulate 25 times your annual expenses
2. In the first year, withdraw 4% of the portfolio
3. Each year, increase the withdrawal by inflation
4. The portfolio (stocks + bonds) continues working

Criticism and limitations

• Based on U.S. data — European markets have historically delivered lower returns
• 30 years may not be enough — FIRE at age 35 means needing 50+ years of withdrawals
• Doesn't account for taxes — In Poland, the Belka tax reduces actual withdrawals
• Sequence of returns — A crash early in retirement is much more dangerous than a mid-retirement crash

Alternatives

• 3.5% rule — More conservative, safer for longer horizons
• Dynamic withdrawals — Reduce withdrawals in bad years, increase in good years
• Guardrails strategy — Set upper and lower withdrawal limits

How Freenance can help

The FIRE calculator in Freenance uses the 4% rule to calculate your financial goal. Based on current expenses, savings, and investment rate, it shows when you'll achieve financial independence.

👉 Calculate your FIRE goal — freenance.io