How Much Do You Need to Retire? The 4% Rule Explained
A simple way to estimate your retirement number using the 4% rule and the 25x guideline, plus what the rule gets right and where it falls short.
"How much do I need to retire?" sounds like it needs a financial advisor and a spreadsheet. In fact, a single, surprisingly simple rule gets you a solid first answer, and it's worth knowing long before retirement is on the horizon.
The 4% rule
The 4% rule comes from research into how much retirees can safely withdraw without running out of money. The idea: in your first year of retirement, withdraw 4% of your invested savings, then adjust that amount for inflation each year after. Historically, a portfolio has had a strong chance of lasting around 30 years at that rate.
Turn it into your number: the 25× rule
Flip the 4% rule around and it gives you a target. If 4% must cover a year's spending, your portfolio needs to be 25 times your annual expenses (because 100% ÷ 4% = 25).
Here's the target for a range of spending levels:
| Annual spending | Retirement target (25×) | First-year 4% withdrawal |
|---|---|---|
| $30,000 | $750,000 | $30,000 |
| $40,000 | $1,000,000 | $40,000 |
| $60,000 | $1,500,000 | $60,000 |
| $80,000 | $2,000,000 | $80,000 |
If you'll have a pension, Social Security or rental income, subtract that from your annual spending first. You only need your portfolio to cover the gap, which can lower your target substantially.
How compounding gets you there
A million dollars sounds impossible until you see what time and consistent investing can do. Thanks to compound growth, regular monthly contributions started early can reach seven figures without heroic saving, the earlier you begin, the less you need to set aside each month.
It was based on historical US markets and a ~30-year retirement. If you retire very early, face a long retirement, or hit a stretch of poor returns early on, a lower withdrawal rate (say 3.5%) may be safer. Treat 4% as a planning anchor, not a promise.
How to use this today
- Estimate your annual spending in retirement (today's money is fine to start).
- Subtract expected pension or state benefits.
- Multiply the remaining gap by 25 to get your target.
- Work out the monthly investing needed to reach it, and start.
See if you're on track. Enter a monthly contribution, return and timeframe to project your retirement pot.
Open the Compound Interest Calculator →The bottom line
Multiply your annual spending by 25 and you have a credible retirement target; withdraw around 4% a year and it has a good chance of lasting. It's an estimate, not a guarantee, but it turns a daunting question into a number you can actually plan toward, starting now.
Frequently asked questions
How much money do I need to retire?
A common guideline is 25 times your annual spending. If you expect to spend $40,000 a year, you'd target around $1 million invested. This comes from the 4% rule, which assumes you withdraw 4% of your portfolio in the first year.
What is the 4% rule?
It's a guideline suggesting retirees can withdraw 4% of their portfolio in the first year, then adjust that amount for inflation each year, with a strong chance the money lasts around 30 years.
Is the 4% rule still reliable?
It's a useful starting point but not a guarantee. Long retirements, low returns or high inflation may call for a more conservative withdrawal rate. Treat it as a planning anchor, not a precise promise.