If you’ve read anything about retirement, you’ve bumped into the 4% rule — usually stated with more confidence than it deserves. It’s a genuinely useful starting point, but it’s also widely misunderstood, occasionally misapplied, and the subject of an ongoing debate among the experts who study it. This guide explains the 4% rule in plain English: what it actually says, where it came from, the assumptions hiding inside it, whether it still holds in 2026, and how to test it against your own numbers instead of taking it on faith.
What is the 4% rule?
The 4% rule says you can withdraw 4% of your retirement savings in your first year, then adjust that dollar amount for inflation every year after, with a strong chance your money lasts at least 30 years. On a $1 million portfolio, that’s $40,000 the first year. If inflation runs 3%, you’d withdraw about $41,200 the next year — and so on.
Notice what the rule is not: it’s not “withdraw 4% of whatever your balance is each year.” You set the dollar amount in year one and then just raise it with inflation. That distinction trips up a lot of people.
Where the 4% rule came from
The rule isn’t marketing — it’s research. In 1994, financial adviser William Bengen tested historical U.S. market data and found that retirees who withdrew about 4% (inflation-adjusted) survived even the worst 30-year stretches in history, including the Great Depression and the 1970s. A few years later, the 1998 “Trinity Study” by three Texas professors reached similar conclusions and cemented the 4% figure in the public mind.
The whole point was to find a withdrawal rate that could survive bad luck — specifically, a market crash early in retirement. That resilience is the rule’s real value.
The assumptions hiding inside the rule
The 4% rule only “works” under specific conditions. Change them and the answer changes:
| Assumption | What the rule expects |
|---|---|
| Time horizon | About 30 years of retirement |
| Portfolio mix | Roughly 50–75% stocks, the rest bonds |
| Withdrawals | A fixed amount, rising only with inflation |
| Returns | Future markets behave roughly like U.S. history |
If you retire at 55 and need 40 years, hold mostly cash, or face weaker future returns, the safe rate is lower. If you’re flexible about spending or have a shorter horizon, it can be higher.
A worked example
Say you retire with $750,000:
- Year 1: withdraw 4% — $30,000
- Year 2: if inflation is 3%, withdraw $30,900
- Year 3: raise again with inflation — ~$31,800
You keep giving yourself that inflation-adjusted “paycheck” regardless of what the market does — which is exactly why the early years are so important. To see how a specific balance and spending level play out over a full retirement, run your own numbers free.
Does the 4% rule still work in 2026?
This is where it gets interesting, because the experts disagree — in both directions:
- Bengen himself now says 4% was too conservative. In recent work he argues the true worst-case safe rate is closer to 4.7%, meaning many retirees who stuck rigidly to 4% left money on the table.
- Morningstar’s 2025 research is more cautious, putting the safe starting rate around 3.9% (up slightly from 3.7% the year before). Their method uses forward-looking return projections rather than past history, which is why their number drifts year to year.
So who’s right? Both, sort of. The honest reading is that the “safe” rate is a range, roughly 3.9% to 4.7%, depending on your assumptions, flexibility, and how the next decade actually unfolds. Treating any single figure as gospel is the real mistake.
The 4% rule’s blind spots
Even at its best, the rule has limits worth knowing:
- It ignores flexibility.Real retirees don’t spend a rigid inflation-adjusted amount through a crash — they cut back, which dramatically improves their odds.
- It’s vulnerable to bad timing.The rule’s biggest enemy is a market drop in your first few years, known as sequence of returns risk.
- It ignores taxes and fees, which quietly reduce what you actually get to spend.
- It assumes you want level spending, when most retirees naturally spend more early and less later.
Better than a rule: test your own rate
Smarter strategies — like “guardrails” that nudge spending up in good years and down in bad ones — can safely support higher withdrawals than a rigid 4%. But the only way to know what’s safe for you is to pressure-test your specific plan. Instead of trusting one number, stress-test your withdrawal rate against 1,000 market scenarios free, including the bad-early-years cases the 4% rule was built to survive. For the bigger picture, see how long your savings will last in retirement.
Frequently asked questions
How much money do I need for the 4% rule to work?
Work backwards from spending: multiply the annual income you want from savings by 25. To draw $40,000 a year at 4%, you’d want about $1 million. To draw $20,000, about $500,000.
Is the 4% rule still accurate in 2026?
It’s still a reasonable anchor, but the “safe” range is debated — roughly 3.9% (Morningstar’s cautious 2025 figure) to 4.7% (Bengen’s updated estimate). Your right number depends on your time horizon, investment mix, and spending flexibility.
Does the 4% rule include Social Security?
No. The rule covers only withdrawals from your portfolio. Social Security and pensions reduce how much you need to withdraw, which makes a given balance last longer.
What’s the biggest risk to the 4% rule?
A poor sequence of returns — a market downturn in the first several years of retirement while you’re withdrawing. It can do far more damage than the same downturn later on.
This article is for educational purposes only and is not financial advice. Everyone’s situation is different. See our full disclaimer.
Sources: William Bengen (1994) and “A Richer Retirement” (2025); Cooley, Hubbard & Walz, “Trinity Study” (1998); Morningstar, “The State of Retirement Income” (2025). See our methodology.