For three decades, William Bengen’s 4% rule has shaped how advisers and retirees think about sustainable withdrawals. Originally published in 1994, the rule suggested that a retiree could withdraw 4% of their portfolio in the first year (gross of fees), increase that amount with inflation, and reasonably expect their funds to last 30 years. But does that guidance still hold in 2026? Recent research and Bengen himself suggest it may no longer be the optimal starting point.
Article last updated 18 June 2026.
