After decades of saving, it's time to start spending once you enter retirement. But how much can you safely withdraw each year without needing to worry about running out of money? The answer is critical, as retirement can last 25 years or more these days, so you need a strategy that's built for the long haul.

A Sustainable Withdrawal Rate

The sustainable withdrawal rate is the estimated percentage of savings you’re able to withdraw each year throughout retirement without running out of money.

We did the math—looking at history and simulating many potential outcomes—and landed on this: For a high degree of confidence that you can cover a consistent amount of expenses in retirement (i.e., it should work 90% of the time), aim to withdraw no more than 4% to 5% of your savings in the first year of retirement, and then adjust the amount every year for inflation.

Of course, your situation could be different. For example, you might want to withdraw more in the early years of retirement when you plan to travel extensively, and less in the later years. But this 4%-to-5% estimate offers a handy guideline for planning.

Let's look at a hypothetical example. John retires at age 67 with $500,000 in retirement accounts. He decides to withdraw 4%, or $20,000, each year for expenses. Since John plans on withdrawing an equivalent inflation-adjusted amount from savings throughout his retirement, this $20,000 serves as his baseline for the years ahead. Each year, he increases that amount by the rate of inflation—regardless of what happens to the market and the value of his investments.

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