Safe Withdrawal Rate Explained
Understand what withdrawal rates mean, why 4% is often discussed, and why no rate is guaranteed.
5 min read
What a withdrawal rate is
A withdrawal rate is the percentage of a portfolio withdrawn for spending in a year. If a portfolio is 1,000,000 and annual spending is 40,000, the withdrawal rate is 4%.
In FIRE calculators, withdrawal rate often converts annual expenses into a target portfolio size.
Why 4% appears often
The 4% rule is a commonly discussed retirement planning heuristic. It is not a law and may not fit every country, tax situation, asset allocation, or retirement length.
Lower rates usually imply larger targets and potentially more resilience. Higher rates imply smaller targets but greater risk.
What affects sustainability
Market returns, inflation, spending flexibility, taxes, portfolio allocation, and sequence risk all affect whether withdrawals remain sustainable.
A calculator can estimate the target, but it cannot guarantee a portfolio will support spending indefinitely.
Key takeaway
Withdrawal rates are planning assumptions, not guarantees. Treat them as part of a wider retirement risk discussion.
Use the calculators
After reading this guide, you can return to the CompoundX calculators to compare your own assumptions. Results are estimates only and do not constitute investment advice.
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