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

Divide your expected annual retirement spending by 4% — or equivalently, multiply it by 25. If you need $50,000 per year, you need $1.25 million saved. If you need $80,000 per year, you need $2 million. This shortcut is called the '25x rule' and comes directly from the 4% withdrawal rate.

Is the 4% rule still realistic in 2025?

Many financial planners now recommend a 3.3%–3.5% withdrawal rate as a safer target, given lower bond yields and higher equity valuations compared to the 1990s data the original study used. The 4% rule succeeds in roughly 90–95% of historical 30-year scenarios but may be riskier for retirements lasting 35–40 years. A flexible strategy — spending a bit less in down years — significantly improves the odds.

What is sequence of returns risk in retirement?

Sequence of returns risk is the danger of a major market crash in the early years of retirement. If your portfolio drops 30% in year one and you keep withdrawing, you sell shares at low prices and lock in losses. The same average return over 30 years produces wildly different outcomes depending on when the bad years hit. Mitigations include keeping 1–2 years of expenses in cash, reducing discretionary spending in down markets, and using a bucket strategy.

What Is the 4% Rule for Retirement? Does It Still Work?

August 23, 2026 · 8 min read

The 4% rule for retirement is the most widely cited guideline in personal finance: withdraw 4% of your portfolio in your first year of retirement, adjust for inflation each year after that, and — based on historical data — your money should last at least 30 years. It's simple, memorable, and frequently misunderstood. This guide explains where it came from, how to apply it, what it actually means for your savings target, and whether it still holds up today.

Where the 4% rule came from

The 4% rule was born from the Trinity Study, a 1994 paper by three finance professors at Trinity University (later updated in 1998 and again in 2011). They backtested withdrawal rates against every 30-year retirement window from 1926 to 1995, using portfolios ranging from 100% stocks to 100% bonds.

Their conclusion: a portfolio of 50–75% stocks and 25–50% bonds, with a 4% initial withdrawal rate adjusted for inflation each year, succeeded — meaning the portfolio lasted the full 30 years — in roughly 95% of all historical scenarios. The 3% rate succeeded in nearly every scenario; the 5% rate failed in a meaningful portion of them. The 4% figure landed in the middle as the practical sweet spot.

Financial planner William Bengen had reached the same conclusion independently and published it the same year, giving the rule its staying power. It wasn't a guess or a marketing rule — it was data-driven, tested against the Great Depression, World War II, 1970s stagflation, and every other historical stress period.

How the 4% rule actually works

The mechanics are straightforward:

Year 1: Withdraw 4% of your starting portfolio balance.
Year 2 and beyond: Withdraw the same dollar amount as the prior year, adjusted upward for inflation.

Notice that you do not recalculate 4% of your current balance each year — you recalculate based on inflation, not portfolio value. This matters. If your portfolio grows in year one, you don't take more. If it falls, you don't automatically take less (though taking less voluntarily is one of the best ways to extend your money's lifespan).

A real example: $1 million portfolio

You retire with $1,000,000. Inflation runs at roughly 3% per year.

Year 1: Withdraw $40,000 (4% of $1,000,000)
Year 2: Withdraw $41,200 ($40,000 × 1.03)
Year 3: Withdraw $42,436
Year 10: Approximately $52,000
Year 20: Approximately $72,000

Your annual withdrawal grows over time to maintain your purchasing power — but the initial $40,000 is the anchor. Whether your portfolio is up to $1.4 million or down to $700,000, you continue adjusting from that original $40,000 baseline, not from your current balance. This makes the math predictable for planning, even though markets are not.

The 25x rule: how much do you need to retire?

The 4% rule is mathematically equivalent to a simple savings target: save 25 times your expected annual retirement spending. This is called the 25x rule and is the most useful way to frame your retirement number.

Need $40,000/year in retirement? Target: $1,000,000
Need $60,000/year in retirement? Target: $1,500,000
Need $80,000/year in retirement? Target: $2,000,000
Need $100,000/year in retirement? Target: $2,500,000

Social Security and any pension income count against your spending need. If you expect $24,000/year from Social Security and need $70,000 total, your portfolio only needs to cover $46,000 — which means a target of $1,150,000 instead of $1,750,000. That's a significant difference.

Use the retirement calculator to plug in your specific numbers — current savings, monthly contributions, expected return, and your target retirement date — to see whether you're on pace for your 25x number.

Does the 4% rule still work in 2025?

This is where honest financial planning gets uncomfortable. The short answer: it works in most historical scenarios, but there are legitimate reasons to be more conservative today.

The case for a lower rate

The Trinity Study used data ending in the mid-1990s, when bond yields were substantially higher than they are now. A 60/40 portfolio in 1994 was earning 6–7% on the bond side alone. Today's bonds yield far less. If the future looks more like 2010–2025 than 1950–1990, the math gets tighter.

Researchers at Morningstar and other institutions have run updated analyses suggesting that, for a 30-year retirement starting in 2024, a 3.3%–3.7% withdrawal rate is safer if you want a 90%+ success probability. For a 40-year retirement (retiring at 55, say), the safe rate may be closer to 3%.

This doesn't mean 4% is wrong — it means it's a guideline, not a guarantee. Many retirees do fine at 4% because they're flexible with spending. Others who rigidly withdraw 4% regardless of market conditions run into trouble.

The flexibility factor

The single best improvement to the 4% rule isn't changing the rate — it's adding flexibility. Research consistently shows that retirees who reduce discretionary spending by 10–15% in years when their portfolio is down significantly extend their portfolio's lifespan without meaningfully changing their quality of life. A few leaner years early in a downturn, rather than forcing the portfolio to sell at market lows, preserves the compounding engine for recovery years.

Rigid adherence to an inflation-adjusted withdrawal regardless of portfolio performance is the version of the 4% rule most likely to fail. Dynamic withdrawal strategies — where you set a floor and ceiling rather than a fixed dollar amount — capture most of the benefit at far lower risk.

What the 4% rule doesn't account for

Even as a starting point, the 4% rule has blind spots worth knowing:

Healthcare costs. Medical expenses in retirement often grow faster than general inflation — especially in the US. If your spending is heavily weighted toward healthcare, your real purchasing-power needs may rise faster than CPI adjustments cover.
Sequence of returns risk. A 30% market crash in year one of retirement, while you're still withdrawing, is far more damaging than the same crash in year 15. Selling low early in retirement locks in losses that compound over time. The 4% rule works on average but not always in the order that markets deliver returns.
Your specific time horizon. The Trinity Study targeted 30-year retirements. If you retire at 55 and live to 90, you need 35 years of coverage — a harder target. The 4% rule's success rate drops as the time horizon extends.
Taxes. The rule assumes pre-tax withdrawals. If your nest egg is in a traditional 401(k), you owe ordinary income tax on every withdrawal. Your effective spending power may be 20–30% lower than the gross withdrawal amount.

Building toward your 25x number

Knowing your target is the easy part. Getting there requires compound growth over time. The earlier you start, the less you need to contribute each month — because compounding does more of the lifting.

A few illustrations at a 7% average annual return (a reasonable long-run estimate for a diversified equity portfolio):

Targeting $1,500,000 in 30 years: contribute approximately $1,440/month
Targeting $1,500,000 in 25 years: contribute approximately $2,200/month
Targeting $1,500,000 in 20 years: contribute approximately $3,600/month

Ten extra years of saving reduces your required monthly contribution by 60%. That's the force of compounding from the other direction — when your money is working longer, you need less from your paycheck.

Use the compound interest calculator to model how your current savings grow to your target, then compare against the retirement calculator to see the full picture with contribution projections and your target retirement date.

Find your retirement number with the 4% rule

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Putting the 4% rule to work

The 4% rule is a starting point, not a finished plan. It gives you a concrete savings target — 25x your annual spending — that you can work toward with monthly contributions, employer matches, and tax-advantaged accounts. It tells you roughly what rate of withdrawal is sustainable over a multi-decade retirement.

Where it doesn't help: it can't predict the specific return sequence you'll experience, your actual healthcare trajectory, or how long you'll live. Those uncertainties argue for being a bit more conservative — 3.5% rather than 4% if you can manage it — and for staying flexible about spending in down years.

For a deeper look at whether your current savings are tracking toward a comfortable retirement, see our guide on whether you're on track for retirement — it walks through benchmark savings rates by age and how to close the gap if you're behind.