Is the 4% Rule Still Safe in 2026? What the Latest Research Actually Says

The 4% rule is probably the single most repeated number in retirement planning — take 4% of your portfolio in year one, adjust that dollar amount for inflation every year after, and your money should last 30 years. It's also more misunderstood than almost any other rule of thumb in personal finance, and the research behind it has moved considerably since it was first published.

Where the 4% Rule Actually Came From

Financial planner William Bengen introduced the concept in 1994, testing every 30-year retirement period in U.S. market history going back to 1926 against a 50/50 stock-and-bond portfolio. His finding: 4.15% was the highest withdrawal rate that would have survived every single historical period without running out of money. That got rounded down to the now-famous "4%."

Critically, it's not "withdraw 4% of your current balance every year." It's a fixed dollar amount, set once in year one, that only gets adjusted upward for inflation afterward — the withdrawal never gets recalculated off your portfolio's current value.

Where the Number Stands in 2026

Two of the most-cited voices in this research have landed in different places for 2026, and the gap between them says a lot about how much judgment is still involved:

• Bengen himself has revised his own number upward, now suggesting a "SAFEMAX" in the 4.7%–5.5% range for current retirees using a more diversified portfolio than his original study.
• Morningstar's 2026 State of Retirement Income report puts the baseline safe starting rate at a more conservative 3.9%, based on forward-looking capital market forecasts rather than historical averages — and that's for a 90% probability the money lasts 30 years, not a guarantee.

On a $1 million portfolio, that's the difference between an initial withdrawal of $39,000 and one closer to $47,000–$55,000 a year. Neither number is "wrong" — they're built on different assumptions about future market returns, and reasonable researchers currently disagree by a meaningful margin.

The Real Risk the 4% Rule Is Built Around

The reason a "safe" rate has to be conservative at all is sequence-of-returns risk: a market downturn in your first few retirement years does far more damage than the same downturn a decade in, because you're selling shares at depressed prices to fund withdrawals while the portfolio has no time left to recover before you need the money again. The math is asymmetric — a 30% drop in year one of retirement can permanently impair a portfolio in a way the same drop in year twenty never would.

Flexible Strategies Can Do Better Than a Fixed Rate

Morningstar's research also found that retirees willing to adjust spending based on market conditions — spending less in down years, more in good ones, rather than a fixed inflation-adjusted amount — could sustainably withdraw as much as 5.7%. A well-known version of this is the Guyton-Klinger "guardrails" approach: set upper and lower bounds around your withdrawal rate, and adjust spending by a fixed percentage whenever you cross one.

Practical Ways to Improve Your Odds

• Plan for a longer horizon than you think you need. If you're retiring at 65 in reasonably good health, planning to 90 or 95 rather than 85 avoids a nasty surprise late in life.
• Keep a cash buffer. One to two years of essential expenses in cash or short-term bonds means a bad first year in the market doesn't force you to sell stocks at the worst possible time.
• Know what your guaranteed income already covers. If Social Security or a pension handles your essential spending, your portfolio only needs to fund the discretionary part — which gives you far more room to cut back in a downturn without touching your basic needs.
• Remember taxes aren't included. A 4% withdrawal from a traditional IRA or 401(k) isn't 4% of spending power — after federal and state income tax, actual spending power is often closer to 3%–3.2% on tax-deferred withdrawals.

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Bottom Line

The 4% rule isn't obsolete, but treating it as a fixed guarantee never made sense — it was always a research finding about historical worst-case scenarios, not a promise. For 2026, a reasonable starting point sits somewhere between Morningstar's more conservative 3.9% and Bengen's own upward revision toward 4.7%, with the honest answer being that your specific mix of guaranteed income, spending flexibility, and time horizon matters more than picking the "right" single number.

Related reading: How Much Do You Need to Retire? A Simple Way to Find Your Number · What Order Should You Withdraw From Your Retirement Accounts? · What Are Required Minimum Distributions (RMDs) and How Do You Avoid the Penalties?