What is the safe withdrawal rate?
The safe withdrawal rate is the percentage of your portfolio you can withdraw each year with a high probability of not running out of money. It is a planning rule, not a guarantee, because actual returns, inflation, fees, and spending patterns vary.
Why 4%? The Trinity Study explained
The 4% rule comes from US retirement research often called the Trinity Study. It tested historical stock and bond portfolios over 30-year retirements and found that an initial 4% withdrawal, increased with inflation, frequently survived the full period.
Is 4% safe in the UK?
Many UK planners use 4% as a starting point but prefer 3% to 3.5% for longer retirements, lower expected returns, higher platform fees, or a more cautious gilts-heavy portfolio. A lower rate needs a bigger portfolio but gives more margin for difficult markets.
How inflation affects withdrawals
In a classic withdrawal strategy, the first withdrawal is a percentage of the starting portfolio and future withdrawals rise with inflation. This protects spending power, but it also means the pounds withdrawn grow every year, which can put pressure on the portfolio after weak market returns.