Safe Withdrawal Rate

A safe withdrawal rate is the percentage of your starting portfolio you can withdraw in the first year of retirement — then adjust upward for inflation each subsequent year — with a high probability that the money lasts for your full retirement. It is the bridge between a pile of savings and a durable stream of income, and it is one of the most studied questions in personal finance.

The concept exists because retirement spending must be defined in real terms: a retiree's cost of living rises with inflation, so a sustainable plan holds purchasing power constant rather than dollars. The rate that turns out to be safe depends heavily on sequence-of-returns risk — the plan must survive not just average markets but a punishing early crash — as well as on the retirement's length, the portfolio's asset mix, and fees.

The best-known answer is the 4% rule, derived from historical US data for a roughly balanced portfolio over a 30-year retirement. But 4% is a starting point, not a law. Longer retirements argue for a lower rate, perhaps 3% to 3.5%; a willingness to spend flexibly — trimming withdrawals after bad years — can support a higher average rate; and lower expected future returns would push the safe rate down.

Rather than treat any single number as gospel, it is wiser to stress-test your own assumptions. The safe withdrawal calculator on this site lets you vary the rate, expected real return, and horizon to see how long a portfolio lasts, and the simulator's withdrawal mode tests real historical return sequences so you can see how a plan would have fared through actual market history.