The 4% rule says you can withdraw 4% of your portfolio in your first year of retirement, then raise that dollar amount with inflation each year, and have a good chance your money lasts about 30 years. To find your target, multiply the yearly income you want from savings by 25. It is a starting point for planning, not a guarantee, and this guide shows where it works and where it breaks down.
Key takeaways
- The 4% rule comes from US historical data and a 30-year retirement. Your own situation may need a lower or more flexible rate.
- Nest egg needed = yearly spending paid from savings × 25 at 4%, or × 28.6 at 3.5%.
- Each $1 million supports roughly $2,500 to $3,333 a month at withdrawal rates of 3% to 4%, before tax.
- The biggest risks are bad returns early in retirement, a retirement longer than 30 years, fees and taxes.
- Flexible withdrawals, such as guardrails, can make a plan more resilient than a fixed rule.
What is the 4% rule?
The 4% rule is a rule of thumb for how much you can spend from a portfolio without running out of money. In year one you withdraw 4% of the starting balance. In every later year you withdraw the same amount plus inflation, no matter what the market did. A $1,000,000 portfolio therefore pays $40,000 in year one.
The idea comes from financial planner William Bengen, who published research in the Journal of Financial Planningin 1994. He tested every 30-year retirement start date in US history back to 1926 using a mix of stocks and bonds. His worst-case retiree began in 1966, just before a long period of high inflation and weak returns, and could still withdraw a little over 4% in the first year. The "4% rule" is that figure, rounded.
A 1998 paper by three Trinity University professors (Cooley, Hubbard and Walz), usually called the Trinity study, reached a similar conclusion for portfolios holding roughly 50% to 75% stocks. Both studies assume US markets, a fixed 30-year horizon and a diversified portfolio.
How much do you need to retire with the 4% rule?
Divide your yearly spending by 0.04, which is the same as multiplying by 25. Use the amount your savings must cover, not your total spending. Social Security, a pension or rental income can pay part of it. The table also shows 3.5% and 3%, which more cautious planners prefer.
| Yearly spending from savings | Nest egg at 4% (×25) | Nest egg at 3.5% (×28.6) | Nest egg at 3% (×33.3) |
|---|---|---|---|
| $30,000 | $750,000 | $857,143 | $1,000,000 |
| $40,000 | $1,000,000 | $1,142,857 | $1,333,333 |
| $60,000 | $1,500,000 | $1,714,286 | $2,000,000 |
| $80,000 | $2,000,000 | $2,285,714 | $2,666,667 |
Social Security matters here. If you want $40,000 a year and expect $20,000 from Social Security, your portfolio only has to cover $20,000, so the 4% target is $500,000 instead of $1,000,000. You can estimate your benefit on the Social Security Administration website.
How much monthly income will my savings produce?
Multiply the portfolio by the withdrawal rate and divide by 12. These figures are before tax and ignore Social Security and other income.
| Portfolio | At 3% | At 3.5% | At 4% |
|---|---|---|---|
| $500,000 | $1,250 a month | $1,458 a month | $1,667 a month |
| $1,000,000 | $2,500 a month | $2,917 a month | $3,333 a month |
| $1,500,000 | $3,750 a month | $4,375 a month | $5,000 a month |
To see what your own savings could grow to before you retire, use the retirement calculator. It applies a withdrawal rate to your projected nest egg and shows the result in today's money.
Why does inflation matter for withdrawals?
The rule raises your withdrawal each year, so the dollar amount grows even if your portfolio does not. At 3% inflation, a $40,000 first-year withdrawal grows to about $53,757 after 10 years of increases, $72,244 after 20 and $97,090 after 30. The inflation calculator shows how fast prices can erode a fixed income.
What are the limits of the 4% rule?
Sequence-of-returns risk
Poor returns early in retirement hurt more than poor returns later, because you are withdrawing from a shrinking balance. The example below uses a $1,000,000 portfolio and a $40,000 first withdrawal that rises 3% a year. Both retirees get the same ten annual returns, in opposite order. The average return is identical, yet the outcomes differ sharply. Each withdrawal is taken at the start of the year, before that year's return. This is a hypothetical illustration, not a forecast.
| Balance after year | Good returns first | Bad returns first |
|---|---|---|
| 1 | $1,094,400 | $768,000 |
| 3 | $1,250,014 | $581,100 |
| 5 | $1,333,256 | $556,487 |
| 10 | $842,097 | $555,610 |
The returns were +14%, +10%, +12%, +8%, +6%, +5%, +7%, −5%, −10% and −20%, and the reverse. After ten years the second retiree has about $286,000 less, and the withdrawals are still rising.
Longer retirements
The studies used 30 years. If you retire at 50 or 55, you may need money for 40 or 45 years, and a lower starting rate is more prudent. The reverse also holds: a shorter horizon or a late start can justify a higher rate.
Fees and taxes
The historical results ignored investment costs and taxes. A 1% annual fee on a $1,000,000 portfolio costs $10,000 a year, a quarter of a $40,000 withdrawal. Withdrawals from traditional 401(k) or IRA accounts are generally taxed as income. If 15% of a $40,000 withdrawal went to tax, you would keep $34,000. Treat the 4% as a pre-tax figure and plan for the tax bill separately. Fees compound over time, as the compound interest calculator makes clear.
What are the alternatives to a fixed 4% withdrawal?
| Approach | How it works | Trade-off |
|---|---|---|
| Fixed 4% rule | Withdraw 4% in year one, then adjust for inflation. | Simple and predictable, but ignores market conditions. |
| Fixed percentage | Withdraw a set percentage of the current balance every year. | The portfolio never runs out, but income moves with the market. |
| Guardrails | Start at a chosen rate. Cut spending if the rate climbs above an upper limit; raise it if the rate falls below a lower limit. | Higher starting income is possible, but you must accept occasional cuts. |
| Required minimum distributions | Withdraw a percentage based on age, following IRS tables. | Adapts to a shrinking horizon, but starts low and rises with age. |
Flexibility is the cheapest protection: skipping an inflation raise after a bad year can matter more than a fraction of a percentage point in the starting rate. The IRS publishes the required minimum distribution rules for US retirement accounts.
How should I use the 4% rule in my own plan?
- Estimate your yearly spending in retirement and subtract guaranteed income such as Social Security or a pension.
- Multiply the gap by 25 for a baseline target, and by about 28.6 for a more cautious one.
- Compare the target with your projection. Use the savings goal calculator to see what monthly amount closes the gap, or the SIP calculator to model regular investing.
- Choose a withdrawal approach you can live with, and decide in advance what you would cut in a bad year.
- Review the plan every year or two and update the numbers.
If you are still building your savings, our guide to how much you should have saved by age shows common benchmarks and what it takes to catch up. The Rule of 72 is a quick way to see how long money takes to double along the way.
Common mistakes with the 4% rule
- Treating 4% as a guarantee, rather than a historical result.
- Using total spending instead of the amount your savings must cover.
- Forgetting taxes, fees and healthcare costs.
- Planning for 30 years when retirement could last 40 or more.
- Ignoring inflation when estimating how far a target will go.
- Having no plan for spending cuts if markets fall early.
What about the UK and Europe?
The 4% rule was built on US data. Research that tested other countries' market histories has found lower sustainable rates in several of them, so many UK and European planners use a more cautious figure.
In the UK, the State Pension changes the sum. The full new State Pension was £230.25 a week in 2025/26, about £11,973 a year, and it rises each year; check the GOV.UK State Pension page for the current amount. Using that 2025/26 figure, if you want £30,000 a year the portfolio only needs to cover about £18,027 (recalculate with the current rate, which will be higher). At 4% that is £450,675, and at 3.5% about £515,057.
UK savers usually draw income through pension drawdown, where you take money from an invested pension pot as you need it. Up to 25% of the pot can generally be taken tax free, and the rest is taxed as income. Drawdown carries the same market-risk questions as the 4% rule. The independent MoneyHelper service explains the options. In much of continental Europe, state pensions replace a larger share of earnings, so the personal portfolio often has a smaller job to do. Rules differ widely by country.
Frequently asked questions
Is the 4% rule still safe?
It has never been guaranteed. It held up in nearly all 30-year periods in the original US studies' historical data, but future markets can differ. Using 3.5% or a flexible method adds a margin of safety.
This guide is general information, not personal financial advice. Returns are never guaranteed, and a licensed adviser can review your own situation.