The “4% Rule” in UK Retirement Planning is a widely used guideline that suggests retirees can withdraw 4% of their starting pension pot each year, adjusting the amount for inflation in future years, with a strong likelihood of their savings lasting at least 30 years. Developed by William Bengen in the 1990s, this approach is based on historical stock and bond market data and assumes a well-diversified portfolio. How It Works Initial Withdrawal: In your first year of retirement, you take 4% of your total pension pot. Subsequent Withdrawals: In each following year, you withdraw the same amount in monetary terms as the previous year, but increased to keep pace with inflation. Example: With a pension pot of £500,000, the first-year withdrawal would be £20,000. If inflation is 2%, your second-year withdrawal would be £20,400. Assumptions: Typically based on a balanced portfolio of around 50% stocks and 50% bonds, without major changes to investment strategy or withdrawal patterns. Sustainability: Intended to make savings last for about 30 years, although actual results can vary depending on market performance and spending behaviour. Potential Risks: Factors such as market volatility, unexpected costs, or above-average inflation can affect how well the 4% rule works in practice.