Safe Withdrawal Rate
How much can you withdraw each year without running out? The answer depends on your time horizon, portfolio mix, and how much risk you can sleep through. This page covers the 4% rule (where it came from, what it actually means, why it works in most historical scenarios), when it breaks, and what to do if you want to be more conservative or more flexible.
Not Financial Advice
The calculator on this page uses simplified projections. It doesn't model taxes, Social Security, sequence of returns, or changes in personal circumstances. Use the result as a planning anchor, not a forecast. A qualified advisor can build a more complete model for your specific situation.
The 4% rule
Test your withdrawal rate
What the 4% rule actually says
In 1994, financial planner William Bengen analyzed historical US market returns and concluded that a 4% initial withdrawal rate — adjusted each year for inflation — never exhausted a 50/50 stock/bond portfolio over any 30-year period in history. The Trinity Study (1998) confirmed similar success rates across portfolio allocations.
The shorthand: 25 × your annual expenses = your FIRE number.
$50,000/year expenses × 25 = $1,250,000 FIRE number
4% of $1,250,000 = $50,000/year
Where the 4% number came from
In 1994, financial planner William Bengen published a study asking: what initial withdrawal rate, adjusted annually for inflation, would have survived every 30-year window in historical US market returns? His answer was 4%. A 50/50 stock/bond portfolio, withdrawing 4% of the starting balance in year 1, then adjusting that dollar amount for inflation each year after, would never have run out in any 30-year period from 1926 to 1976 (the historical data he had at the time).
The 1998 Trinity Study, by three professors at Trinity University, extended and stress-tested Bengen's work across multiple portfolio allocations and historical periods. The result broadly confirmed: 4% worked across most 30-year windows, 3% worked in essentially every window including the worst historical sequences, and 5% started to fail in bad market periods.
The shorthand: 25 × your annual expenses = your FIRE number. $50,000/year expenses × 25 = $1,250,000. 4% of $1,250,000 = $50,000/year. The math is the same forward or backward.
Why 4% isn't guaranteed
The 4% rule is based on historical data. It assumes a 50/50 stock/bond mix, constant annual inflation adjustments, and a 30-year horizon. Sequence of returns risk — a market crash early in retirement before recovery — is the biggest threat. A 50% drop in year one with $40,000 withdrawals is far more damaging than the same drop in year twenty.
Dynamic withdrawal strategies
- Variable withdrawal — Withdraw a fixed percentage of your portfolio each year (e.g., 4%). Falls in downturns, rises in bull markets.
- Guardrail method — Start at 4%. Reduce spending 10% if portfolio drops 20%. Increase if it doubles.
- Ratchet method — Raise spending when portfolio hits new highs. Never cut.
Withdrawal rates by horizon
| Years in Retirement | Safe Rate | FIRE Multiple |
|---|
| 20 years | 5.0% | 20× |
| 25 years | 4.5% | 22× |
| 30 years | 4.0% | 25× |
| 35 years | 3.7% | 27× |
| 40 years | 3.5% | 29× |
| 50 years | 3.2% | 31× |
The practical takeaway
The real question is not "what's the safest rate" but "what withdrawal rate gives me confidence I never have to go back to work?" For a 30-year retirement, 3.5–4% is the reasonable range. For early retirees planning 40–50 years, 3–3.5% is more conservative.
Sequence of returns: the actual risk
The 4% rule assumes your portfolio grows at the historical average. The risk is not the average — it's the order of returns. A 30% crash in year 1 of retirement, followed by mediocre returns for the next 5 years, is much worse than a 30% crash in year 25. Same average, very different outcomes.
Sequence-of-returns risk is why the 4% rule is calibrated for a 30-year horizon with annual inflation adjustments, not a constant-dollar withdrawal. Adjusting for inflation means your withdrawal amount grows each year; if the market is in a slump and you withdraw the same nominal amount, you erode the portfolio faster. The constant-real-withdrawal approach smooths this out.
For early retirees, the risk is amplified by the longer horizon. A 60-year-old retiring today might have a 30-year horizon; a 35-year-old retiring today might have a 60-year horizon. The historical data is thinner on 60-year windows, and the math gets tighter. This is why early retirees often plan on 3-3.5% rather than 4%.
The role of Social Security and other income
The 4% rule assumes the entire portfolio is generating the withdrawal. In practice, most retirees have other income sources: Social Security benefits, a pension, part-time work, rental income. Each of those reduces what the portfolio has to cover, which means you can withdraw more than 4% of the portfolio and still be safe.
A common rule of thumb for Social Security: claiming at age 67 (full retirement age for people born in 1960 or later) gives you about $X/year in benefits (varies widely by lifetime earnings). If your annual expenses are $50K and Social Security covers $24K of that, the portfolio only needs to cover $26K — and at 4% of a $650K portfolio, that works. The portfolio can be smaller, or the withdrawal rate can be higher, than the pure 4% rule suggests.
Why most retirees spend less than they think
Empirical studies of retirement spending consistently find that retirees spend less over time, not the same or more. Travel-heavy early retirement gives way to quieter, less expensive decades. Healthcare costs do rise, often substantially, but the offset is real.
The practical implication: a 4% initial withdrawal rate, even with no adjustments for declining spending, tends to be conservative for most retirees. The biggest risk in retirement is not running out of money — it's spending too little because you're worried about running out. The 4% rule balances those concerns; pulling less than 4% gives up lifestyle now for an unlikely-tail benefit later.
How to use the calculator on this page
Enter your starting portfolio, your planned annual withdrawal, the number of years you expect to withdraw, and your assumptions for return and inflation. The calculator shows you the projected end balance and the "real" (after-inflation) return. Negative ending balances mean the portfolio ran out before the end of the horizon.
Use the calculator to stress-test specific scenarios, not to predict the future. Real returns vary; the historical 7% nominal / 3% real is a planning assumption, not a forecast. A more conservative planner might use 6% / 4% or 5% / 3% to see how the numbers change.
Related reading
The safe withdrawal rate is the other half of the FIRE equation — compound interest (covered in the compound interest guide) is the wealth-building side, SWR is the wealth-withdrawal side. The Coast FIRE calculator uses the same SWR assumption to compute your target portfolio value. The Progress Tracker shows where you are relative to that target today.
This calculator uses simplified projections. Does not account for taxes, sequence of returns, or changes in personal circumstances. Not financial advice. See our Editorial Policy for how we approach this content.