The 4 Percent Rule and Whether It Still Holds Up

You have a retirement balance on a screen and no clear idea how much of it you can spend each year without running out at 85. The 4 percent rule is the most common answer people reach for, and it gives a real starting number in about ten seconds. The harder question is whether that number fits your retirement, and that is what this article works through.

I have run this math with dozens of readers who wrote in with their balances, and the pattern is consistent. The rule is a useful planning anchor and a poor autopilot. Here is how it works, where it came from, and the adjustments that matter.

What the 4 percent rule actually says

The rule says you can withdraw 4 percent of your portfolio in your first year of retirement, then raise that dollar amount by inflation each year after, and have a high chance of the money lasting 30 years.

The math is simple:

A $500,000 portfolio supports a first-year withdrawal of $20,000.
A $1,000,000 portfolio supports $40,000.
If inflation runs 3 percent, the $40,000 becomes $41,200 in year two, regardless of what the market did.

Flip it around and you get the popular "25 times" target. If you need $50,000 a year from savings, multiply by 25 and you get $1,250,000. That number is the portfolio size the rule suggests you need before you stop working.

Where the number came from

The figure traces back to a 1994 study by financial planner William Bengen. He tested withdrawal rates against historical US market returns going back to 1926, using a portfolio split roughly between stocks and intermediate government bonds. He looked for the highest starting withdrawal that survived every 30-year period in the data, including retirements that began just before the Great Depression and in the high-inflation late 1960s.

That worst-case starting rate landed a little above 4 percent. A later analysis from three Trinity University professors, often called the Trinity study, reached similar conclusions using a range of stock and bond mixes.

The key detail is that 4 percent was the survivable rate in the worst historical stretch. In most 30-year periods, retirees following the rule ended with more money than they started with, sometimes much more.

Why the 4 percent rule can be too cautious

Most articles on this topic warn that 4 percent is too aggressive. I think the more common mistake runs the other way. Because the rule was built around the worst sequence of returns on record, a retiree who follows it rigidly in an average market often dies with a large unspent balance.

Consider a couple retiring at 65 with $1,000,000 in a 60/40 portfolio. Under the rule they spend $40,000 in year one. If returns are close to historical averages, their balance can grow well past $1,500,000 by their late 70s while they keep spending the same inflation-adjusted amount. Those were their most active years, and the money sat idle.

The rule also ignores other income. If Social Security covers $30,000 of a $70,000 budget, the portfolio only needs to supply $40,000. Our guide to when to claim Social Security shows how delaying to 70 raises that guaranteed floor, which lets the portfolio carry less of the load.

None of this means you should start at 6 percent. It means the rule is a floor for planning, not a ceiling on spending once you see how markets actually behave.

When the 4 percent rule is not enough

There are also situations where 4 percent is genuinely risky:

Early retirement. The rule was tested for 30 years. If you retire at 50 and need the money to last 40 to 45 years, research generally points to something closer to 3.25 to 3.5 percent.
High fees. If you pay a 1 percent advisory fee plus fund costs, that comes straight out of your safe withdrawal. A 4 percent rule with 1.2 percent in total fees behaves more like a 5.2 percent withdrawal.
Very conservative portfolios. The original testing assumed at least half the money in stocks. A portfolio held mostly in cash and short-term bonds may not keep up with inflation over three decades.
A bad first few years. Sequence-of-returns risk means a 25 percent drop in year one hurts far more than the same drop in year fifteen, because you are selling shares at low prices to fund spending.

Simple adjustments that make the rule work better

You do not have to choose between blind faith in 4 percent and a complicated plan. A few guardrails cover most of the risk:

Skip the inflation raise after a down year. If your portfolio lost money last year, keep this year's withdrawal flat. This small change meaningfully improves how often the plan survives in historical testing.
Set a ceiling and a floor. One common approach: if your current withdrawal climbs above 5 percent of the current balance, cut spending by 10 percent. If it falls below 3 percent, give yourself a 10 percent raise.
Hold one to two years of spending in cash. This lets you avoid selling stocks during a sharp drop. For a $40,000 withdrawal, that is $40,000 to $80,000 in a high-yield savings or money market account.
Withdraw from the right accounts. The order you tap taxable, traditional, and Roth accounts affects how long the money lasts after tax. Our explanation of what a Roth IRA actually does covers why tax-free withdrawals are often worth saving for later years.

Using the rule while you are still saving

For people a decade or more from retirement, the 25 times target is mostly useful as a progress check. If you expect to need $45,000 a year from savings, your target is about $1,125,000 in today's dollars. Divide your current balance by that number and you get a rough percentage of the way there.

If that percentage looks low for your age, the fix is usually a combination of higher contributions, a slightly later retirement date, and a realistic look at your expected expenses. Our guide on catching up on retirement savings after a late start walks through the contribution limits and catch-up amounts available after 50.

Frequently asked questions

How much do I need to retire using the 4 percent rule?

Multiply the annual income you need from savings by 25. If you need $60,000 a year beyond Social Security and any pension, the rule suggests a portfolio of about $1,500,000. Lower spending or more guaranteed income reduces that target.

Is the 4 percent rule still valid?

It remains a reasonable starting point for a 30-year retirement with a balanced portfolio. Some researchers suggest slightly lower rates when bond yields are low or retirement is longer, while others argue flexible spending can support higher rates. Treat it as a planning baseline, not a guarantee.

Does the 4 percent rule include taxes?

No. The 4 percent is a gross withdrawal, so any income tax owed comes out of that amount. Withdrawals from traditional IRAs and 401(k)s are taxed as ordinary income, while qualified Roth withdrawals are tax-free.