How Much Do I Need to Retire? The 4% Rule Explained

“How much do I need to retire?” sounds like a question with a single answer, but it depends on how you want to live, when you plan to stop working and where your income will come from. The good news: you can get a solid working estimate in about ten minutes, and then turn it into a monthly savings goal you can act on today.

This guide explains the 4% rule, shows how to calculate your retirement number, covers the rule’s limitations and walks you backward from that number to what you need to save each month.

Step 1: Estimate your annual spending in retirement

Start with what you expect to spend each year in retirement, in today’s dollars. Two common approaches:

• Replacement rate: many planners suggest planning for roughly 70–80% of your pre-retirement income, since you’ll no longer be saving for retirement or paying payroll taxes, and some work costs disappear.
• Bottom-up budget: estimate actual costs for housing, food, healthcare, travel, hobbies and taxes.

For someone in their 20s or 30s, a replacement-rate estimate is fine. You’ll refine it as retirement gets closer.

Example: You earn $75,000 and expect to need about 80%, or $60,000 a year in today’s dollars.

Step 2: Subtract guaranteed income

Social Security will likely cover part of your spending. Your estimated benefit depends on your earnings history and the age you claim. You can see a personalized estimate by creating a free account at ssa.gov.

Many younger workers prefer to plan conservatively, assuming somewhat lower benefits than the current estimate, because of uncertainty about the program’s long-term funding.

Example: If you expect about $22,000 a year from Social Security in today’s dollars, your savings need to cover $60,000 − $22,000 = $38,000 a year.

Step 3: Apply the 4% rule

The 4% rule comes from research by financial planner William Bengen in the 1990s and later studies such as the Trinity study. Historically, a retiree who withdrew 4% of their portfolio in the first year of retirement, then adjusted that amount for inflation each year, would have had a high likelihood of their money lasting at least 30 years with a balanced stock and bond portfolio.

Flip it around, and you get a simple target:

Retirement number = annual spending from savings × 25

(Because 4% = 1/25.)

Example: $38,000 × 25 = $950,000 in today’s dollars.

Step 4: Work backward to a monthly savings goal

Now the question becomes: how much do you need to invest each month to get there?

Hypothetical, assuming a constant 7% annual return compounded monthly and starting from $0. Using a nominal return with a target in today’s dollars understates the true need; to be more conservative, use a lower return, such as 5%, to approximate returns after inflation.

Starting 10 years earlier more than halves the monthly amount. Remember that employer 401(k) matching contributions count toward these figures. Our guide to compound interest explains why time matters so much.

Limitations of the 4% rule

The 4% rule is a useful starting point, not a guarantee. Keep these in mind:

• It was designed for a 30-year retirement. If you plan to retire early, at 45 or 50, many planners suggest a lower withdrawal rate, such as 3–3.5%, which means a larger target (28 to 33 times spending).
• Market timing matters. Retiring into a deep market downturn can strain a portfolio, especially in the first few years (“sequence of returns risk”).
• It assumes a specific portfolio. The research generally used a mix of stocks and bonds. Very conservative portfolios may not support the same withdrawal rate.
• Spending isn’t fixed. Many retirees spend more early and less later, or adjust spending in bad markets, which can improve the odds.
• Healthcare and taxes vary. Withdrawals from traditional accounts are taxable, and healthcare costs before Medicare (age 65) can be significant.

Some researchers have suggested safe rates a little above or below 4%, depending on market conditions and assumptions. Treat 4% as a reasonable planning guide, and revisit your plan every few years.

Quick benchmarks to stay on track

If you prefer a simpler check, a widely used guideline suggests aiming for retirement savings of about:

• 1× your salary by 30
• 2× by 35
• 3× by 40
• 10× by 67

See our full guide on how much you should have saved by age.

How to close the gap

If your monthly savings goal feels out of reach, these levers help most:

1. Capture your full employer match. See how a 401(k) works.
2. Increase contributions by 1% a year or every time you get a raise.
3. Use tax-advantaged accounts: 401(k), Roth IRA and HSA.
4. Keep investment fees low with broad index funds.
5. Work a little longer or part-time in early retirement; each extra year adds contributions and shortens the time your savings must last.
6. Delay claiming Social Security; each year you wait past full retirement age (up to 70) increases your benefit.

Example: three paths to the same retirement

Here’s how three people might plan for the same goal: about $50,000 a year from savings in today’s dollars, which means a target of roughly $1.25 million using the 4% rule.

Hypothetical: assumes constant 5% returns after inflation, compounded monthly, starting from $0. Actual returns vary and are not guaranteed. Employer matching contributions count toward these amounts.

Cleo needs about two and a half times as much each month as Ava, because Cleo has 15 fewer years for compounding to do the work. Ben, starting just seven years after Ava, already needs 50% more per month.

Factors that shrink your number

• A paid-off home reduces housing costs in retirement.
• Part-time work in your early 60s reduces how long savings must last.
• Delaying Social Security increases your guaranteed lifetime income.
• Lower expected spending, for example by moving to a lower-cost area.

Factors that grow your number

• Early retirement, which means more years of withdrawals and a lower safe withdrawal rate.
• Healthcare before Medicare, which can be expensive between leaving a job and age 65.
• Supporting family members or high travel goals.

Revisit your estimate every two or three years, or after a big life change such as marriage, children or a career shift.

Frequently asked questions

Is $1 million enough to retire?

It depends on your spending. Using the 4% rule, $1 million supports about $40,000 a year in initial withdrawals, plus Social Security and any other income. For some people that’s plenty; for others, it’s not enough.

Should I include my home in my retirement number?

Usually not, unless you plan to sell or downsize and use the proceeds. Your retirement number typically refers to investments that generate spendable income.

How does inflation affect my retirement number?

Prices rise over time, so $60,000 today will cost much more in 30 years. That’s why planning in today’s dollars and using after-inflation return assumptions is helpful.

What’s the 25× rule?

It’s the 4% rule turned around: multiply your desired annual spending from savings by 25 to estimate your retirement target.

Can I retire early with the 4% rule?

Many early retirees use the rule as a starting point but plan with lower withdrawal rates, flexible spending and other income sources to account for a retirement that may last 40 years or more.

Do employer 401(k) matches count toward my savings goal?

Yes. Employer contributions go into your account and grow alongside your own, so they count toward both your monthly savings target and your final retirement number. If your employer adds 4% of your salary, you need to contribute that much less yourself to reach the same total.

Your retirement number, in four steps

To estimate how much you need to retire: project your annual spending, subtract expected Social Security and other income and multiply what’s left by 25. Then work backward to a monthly savings target. The 4% rule isn’t perfect, but it turns a vague worry into a concrete goal you can track.

Where to start: Create a free account at ssa.gov to see your estimated Social Security benefit, then run the four steps above. Then try different monthly amounts in the compound interest calculator on our Financial Tools page.