The 4% rule for retirement: how it works and its limits

Quick answer: the 4% rule says that if you withdraw 4% of your retirement savings in your first year of retirement, then increase that dollar amount each year with inflation, your money has historically had a high chance of lasting at least 30 years. Flipped around, it gives a quick savings target: multiply your yearly spending from savings by 25.

How the 4% rule works

StepExample
Savings at retirement$1,000,000
Year 1 withdrawal (4%)$40,000
Inflation that year3%
Year 2 withdrawal$41,200
Year 3 (inflation 2.5%)$42,230

You do not recalculate 4% of the balance each year. You take your first-year amount and adjust it for inflation, regardless of how markets did.

The 25x rule: how much do you need?

Because 4% is 1/25, the rule implies you need 25 times the annual income you want from savings.

Income needed from savings each yearSavings target (x25)
$20,000$500,000
$30,000$750,000
$40,000$1,000,000
$60,000$1,500,000
$80,000$2,000,000

Subtract guaranteed income first. If you need $60,000 a year and expect $24,000 from Social Security, you need to fund $36,000 from savings, which is a target of $900,000. See Social Security full retirement age for how claiming age changes that number.

Where the 4% rule comes from

Financial planner William Bengen tested withdrawal rates against US market history back to 1926 and published his findings in 1994. He found that 4% of a portfolio split roughly between stocks and bonds survived every 30-year period in his data. The later “Trinity study” reached similar conclusions.

Limitations to keep in mind

  1. It assumes a 30-year retirement. Retiring at 50 or earlier may call for 3% to 3.5%.
  2. It is based on past US returns. Future returns may be lower or higher.
  3. Sequence of returns risk. A market crash in the first few years of retirement hurts far more than one later.
  4. It ignores fees and taxes. Withdrawals from traditional accounts are taxed, and high fees lower the safe rate.
  5. It is rigid. Real retirees spend less in bad years and more in good ones.

Flexible alternatives

  • Guardrails: raise spending after good years and cut it by a set percentage after bad ones.
  • Percentage of balance: withdraw a fixed percent of whatever the balance is each year. Your money never runs out, but income varies.
  • Bucket strategy: keep 1 to 3 years of spending in cash, so you do not sell investments in a downturn.
  • Guaranteed income: delaying Social Security or buying an annuity covers essentials.

How RMDs fit in

Once you reach RMD age, you may be required to withdraw more than 4% from tax-deferred accounts. You do not have to spend it; you can reinvest it in a taxable account. See required minimum distributions.

Frequently asked questions

Is the 4% rule still valid? Many researchers still see 4% as a reasonable starting point for a 30-year retirement, with some suggesting slightly lower or higher depending on market conditions.

How much can I withdraw from $500,000? About $20,000 in the first year under the 4% rule.

Does the 4% rule include Social Security? No. It applies only to your investment portfolio.

This article is general information, not financial advice. Consider speaking with a fee-only financial planner.