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How Much Do You Need to Retire

"How much do I need to retire?" is one of the most important financial questions you can ask — and the answer is more accessible than most people think. It depends on two things: how much you plan to spend in retirement, and how long your money needs to last.

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How Much Do You Need to Retire

The Core Question

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"How much do I need to retire?" is one of the most important financial questions you can ask — and the answer is more accessible than most people think. It depends on two things: how much you plan to spend in retirement, and how long your money needs to last.

Rather than aiming for an arbitrary number like "$1 million," understanding the underlying math lets you calculate a target that's specific to your actual life.

The 4% Rule

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The most widely used framework is the 4% rule, derived from academic research on long-term portfolio survival rates. It states that a retiree can withdraw 4% of their portfolio in the first year of retirement, adjust for inflation each subsequent year, and have a high probability of the portfolio lasting at least 30 years.

This gives you a simple formula: Required portfolio = Annual retirement expenses × 25

If you expect to spend $50,000 per year in retirement, you need approximately $1,250,000. If $80,000, then $2,000,000.

The 4% rule has critics — it's based on historical US market data and may not hold in all market environments — but it remains a useful benchmark for planning.

Estimating Retirement Spending

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Retirement spending is typically lower than working-life spending, because:

  • Work-related costs disappear (commuting, clothing, lunches)
  • Mortgage may be paid off
  • Children are typically financially independent
  • You're no longer saving for retirement

A common rule of thumb is that retirement spending is roughly 70–80% of pre-retirement spending. However, early retirement years often involve higher spending (travel, experiences), while later years may see lower discretionary spending and higher healthcare costs.

Other Income Sources

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Your portfolio doesn't need to fund all retirement spending. Other income sources reduce how large a portfolio you need:

  • Government pension or Social Security — a significant income floor for most retirees
  • Defined benefit pension — if you have one, it covers a fixed income floor
  • Rental income, part-time work, or other streams — reduce the draw on savings

Subtract guaranteed income sources from your annual spending estimate before calculating your portfolio target.

Educational content only. Not financial, investment, tax or legal advice. Learn more

Quiz me on this
According to the 4% rule, how large does a portfolio need to be to support $60,000 per year in retirement?
  1. $600,000
  2. $1,000,000
  3. ✓ $1,500,000
  4. $2,400,000
What does the 4% rule assume about annual withdrawals after the first year?
  1. Withdrawals stay fixed at exactly 4% regardless of inflation
  2. ✓ Withdrawals increase with inflation each year after the first
  3. Withdrawals decrease by 2% per year as you age
  4. Withdrawals stop entirely if the market falls
Why is retirement spending often lower than pre-retirement spending?
  1. Retirees are required by law to reduce spending
  2. Investment returns eliminate the need for most spending
  3. ✓ Work-related costs, active saving, and often mortgage payments disappear in retirement
  4. Government subsidies replace most discretionary spending
How do guaranteed income sources like Social Security or a pension affect your required retirement portfolio size?
  1. They have no effect — you still need the full portfolio target
  2. They allow you to retire earlier regardless of savings
  3. ✓ They reduce the annual amount your portfolio needs to cover, lowering your required portfolio size
  4. They replace your portfolio entirely if the amounts are high enough