The 30-Second Summary
A common starting point is the 25x rule: multiply your expected annual spending in retirement by 25. That figure comes from the idea that withdrawing roughly 4% per year from a diversified portfolio has historically had a good chance of lasting three decades or more. It's a rule of thumb, not a guarantee — your actual number should account for your own timeline, expenses, and risk tolerance.
1. Working Out Your "Retirement Number"
The most common way to estimate a retirement target starts with your expected annual expenses, not your current income. Many people spend less in retirement than during their working years, since commuting costs, mortgage payments, and retirement contributions themselves often shrink or disappear.
| Annual Spending Need | Target Nest Egg (25x) | Approx. Annual Withdrawal (4%) |
|---|---|---|
| $40,000 | $1,000,000 | $40,000 |
| $60,000 | $1,500,000 | $60,000 |
| $80,000 | $2,000,000 | $80,000 |
| $100,000 | $2,500,000 | $100,000 |
Figures are illustrative estimates for educational purposes only and don't account for taxes, healthcare costs, pensions, or other income sources.
2. Where the 4% Rule Comes From
The 4% guideline originates from research on historical U.S. market returns, which found that withdrawing 4% of a portfolio in the first year of retirement, then adjusting that amount for inflation each year after, kept most portfolios solvent over a 30-year retirement in the majority of historical scenarios.
Why It's Just a Starting Point
The rule was built on historical returns that may not repeat. A longer retirement, a market downturn early on, or higher-than-expected inflation can all mean 4% turns out to be too aggressive for a given individual.
Flexible Withdrawal Strategies
Some retirees adjust spending based on market performance year to year, which can extend a portfolio's life compared to a fixed withdrawal amount.
3. Factors That Move Your Target Up or Down
Your personal retirement number isn't fixed — it shifts based on a handful of variables that are worth revisiting periodically as your life circumstances change.
📊 Key Variables
- Other income sources: Social Security, pensions, or rental income can reduce how much your portfolio needs to cover.
- Healthcare costs: Often one of the largest and least predictable retirement expenses.
- Retirement length: Retiring at 50 requires a portfolio built to last far longer than retiring at 67.
- Location and lifestyle: Cost of living varies enormously between regions and countries.
- Inflation: Even modest inflation compounds significantly over a 20-30 year retirement.
4. Your Portfolio Isn't the Only Piece of the Puzzle
The 25x rule is often applied to total expenses, but most people don't fund retirement from an investment portfolio alone. Government benefits, workplace pensions, rental income, or part-time consulting can all cover a portion of annual spending — which lowers how much the portfolio itself has to provide.
Public Retirement Benefits
Programs like Social Security in the U.S., or state pensions elsewhere, replace a portion of pre-retirement income and can meaningfully reduce the "gap" your savings need to fill. Benefit amounts typically depend on your earnings history and the age you start claiming.
Workplace Pensions
Traditional defined-benefit pensions have become less common, but where they exist, they can provide predictable income that reduces reliance on market-based withdrawals.
Part-Time or Phased Work
Some retirees choose to keep working in a reduced capacity for a few years, which both lowers portfolio withdrawals and delays the point at which the portfolio needs to support 100% of expenses.
Real Estate & Other Assets
Rental income, downsizing a home, or other non-portfolio assets can supplement retirement income, though they come with their own risks like vacancy, maintenance costs, or market timing.
5. Why the Order You Draw Down Accounts Matters
Once retirement begins, the sequence in which money is withdrawn from different account types — taxable brokerage accounts, tax-deferred retirement accounts, and tax-free accounts — can affect how long a portfolio lasts and how much tax is owed along the way.
A common general approach is to draw from taxable accounts first, allowing tax-advantaged accounts more time to grow, though the optimal order depends on individual tax brackets, required minimum distribution rules, and estate planning goals. This is an area where the details genuinely matter and where professional guidance tends to add the most value.
6. Stress-Testing Your Retirement Number
Because a single "expected return" projection can hide a wide range of real-world outcomes, many planners recommend testing a retirement plan against multiple scenarios rather than a single average case.
🧪 Ways to Pressure-Test a Retirement Plan
- Historical sequence testing: Checking how a withdrawal plan would have performed starting in various past years, including ones with early market downturns.
- Monte Carlo simulations: Running thousands of randomized market scenarios to estimate the probability a portfolio lasts through retirement.
- Conservative assumptions: Modeling a plan using lower-than-average expected returns and higher-than-average inflation to see if it still holds up.
- Spending flexibility: Building in the ability to reduce discretionary spending during down markets, rather than assuming fixed spending no matter what.
7. Turning the Number Into a Plan
Once you have a rough target, the next step is working backward to figure out how much you need to save and invest each month to reach it by your desired retirement age. Consistent contributions to a diversified, low-cost portfolio — combined with the effect of compounding over time — are what typically closes the gap between today's savings and tomorrow's number.
It's also worth revisiting the number periodically. Income changes, family circumstances shift, and the cost of living moves over time, so a target set at 25 will likely look different by 40. Treat the calculation as a living estimate rather than a one-time task.
This article is educational and doesn't constitute personalized financial advice. Consider speaking with a licensed financial advisor about your specific situation.