Retirement Withdrawal Calculator

Find out how long your retirement savings will last - or how much you can safely withdraw.

💸 How Long Will Your Retirement Savings Last?

One of the most critical questions in retirement planning is: how long will my money last? The answer depends on three variables: how much you have (portfolio balance), how much you spend (monthly withdrawal), and how much your investments earn (return rate) during the withdrawal phase. This calculator solves this question directly - given a balance and monthly withdrawal at a given return rate, it computes the number of years until the portfolio is depleted.

The 4% rule provides a widely-used benchmark: withdrawing 4% of the initial portfolio annually has historically sustained a 30-year retirement through all market cycles, including the Great Depression and 1970s stagflation. For a $1 million portfolio, this translates to $40,000/year or $3,333/month. Early retirees who need 40–50 years of income often use 3–3.5% to improve sustainability. Conversely, short retirement horizons (10–15 years) can support higher rates (6–8%).

Sequence-of-returns risk - the risk of poor investment returns early in retirement - is the biggest threat to portfolio longevity. A market crash in the first 5 years of retirement can permanently impair a portfolio even if long-run returns recover. This is why most retirement financial planning uses conservative return assumptions (4–5%) during the withdrawal phase rather than the historical 7–10% average.

📐 Portfolio Longevity Formula

n = −ln(1 − PV × r / PMT) / ln(1 + r)

4% Rule Monthly = Balance × 4% / 12

n = Number of months until depletion

PV = Current portfolio balance

r = Monthly return rate (annual / 12)

PMT = Monthly withdrawal amount

This is the standard present-value annuity formula solved for n (number of periods). If PMT ≤ PV × r (monthly withdrawal doesn't exceed monthly earnings), the portfolio lasts indefinitely - your withdrawal rate is at or below the perpetuity threshold. When this condition holds, the portfolio never depletes; it shows as "Indefinite" in the calculator.

📖 How to Use This Calculator

Steps

Enter your portfolio balance - total of all retirement accounts, brokerage accounts, and other investments.

Enter monthly withdrawal - your planned monthly spending from the portfolio (exclude Social Security and pension income, which are separate).

Enter expected return rate - use 4–6% for a balanced portfolio in retirement (more conservative than accumulation phase assumptions).

Click Calculate to see how many years the portfolio lasts, the 4% rule monthly safe amount, and your annual withdrawal rate.

💡 Example Calculations

Example 1 - $1M Portfolio, $4,000/month

Balance = $1,000,000 | Monthly = $4,000 | Return = 5%

Monthly rate r = 5/12/100 = 0.4167%; PMT = $4,000; PV = $1,000,000

n = −ln(1 − 1,000,000 × 0.004167 / 4,000) / ln(1.004167) = −ln(1 − 1.0417) / ... = indefinite (portfolio earns more than withdrawal)

4% rule monthly = $1M × 4% / 12 = $3,333/month | Annual rate = 4.8% - slightly above 4% SWR

Try this example →

Example 2 - $500K Portfolio, $3,500/month

Balance = $500,000 | Monthly = $3,500 | Return = 5%

Annual withdrawal = $42,000 = 8.4% of $500K - well above 4% SWR. Portfolio lasts approximately 18.1 years

Try this example →

❓ Frequently Asked Questions

How long will $1 million last in retirement?+

At a 4% annual withdrawal ($40,000/year) with a 5% annual return, $1 million will last indefinitely (return exceeds withdrawals). At zero return, it lasts 25 years. At a 6% withdrawal ($60,000/year) with 5% return: approximately 28 years. The key is the relationship between the withdrawal rate and portfolio return.

What is the 4% safe withdrawal rule?+

Research by Bengen (1994) found that retirees withdrawing 4% of their initial portfolio per year, adjusted for inflation, historically did not run out of money over 30 years using a 50/50 stock-bond portfolio. For Indian portfolios with higher inflation, a 3-3.5% rate is more conservative.

How do I adjust withdrawals for inflation?+

Multiply your year-1 withdrawal by (1 + inflation rate) each year. At Rs 50,000/month with 6% inflation, year 2 withdrawal becomes Rs 53,000, year 10 becomes Rs 89,542. This calculator shows whether your corpus survives this escalating withdrawal pattern over your planned retirement horizon.

What portfolio return should I assume in retirement?+

A conservative assumption is 7-8% nominal (5-6% real after 2% inflation). Retirees typically shift to 40-60% debt, lowering expected returns. Using 10%+ is optimistic and risks outliving your money. Run scenarios at 6%, 8%, and 10% to understand your range of outcomes.

How long should I plan for my retirement corpus to last?+

Plan for at least 25-30 years post-retirement. With retirement at 60 and life expectancy rising past 85, 30 years is prudent. Factor in spousal longevity - if your spouse is younger, the corpus may need to last 35+ years. Underestimating longevity is the most common retirement planning mistake.

What is the 4% rule?+

The 4% rule states you can withdraw 4% of your initial portfolio in year 1, adjust for inflation annually, and the portfolio will last at least 30 years. Based on a 50/50 stock/bond portfolio and historical US market data, this rule survived all 30-year periods from 1926 onward, including the Great Depression and 1970s inflation.

What withdrawal rate is safe for early retirement?+

For a 30-year retirement: 4%. For a 40-year retirement: 3.5%. For a 50-year retirement (FIRE): 3–3.25%. The longer the retirement, the more sequence-of-returns risk exists - a market crash early in retirement can permanently impair portfolio longevity.

How do I calculate a sustainable monthly withdrawal?+

Sustainable monthly withdrawal = Portfolio Balance × Annual SWR / 12. For $800,000 at 4% SWR: $800,000 × 4% / 12 = $2,667/month. This maintains the real purchasing power of the portfolio over 30 years in most historical scenarios.

What is the 4% safe withdrawal rate rule?+

The 4% rule (Trinity Study, 1994) found that withdrawing 4% in year 1, then adjusting for inflation annually, sustained a 30-year retirement in over 95% of historical scenarios with a 50/50 stock-bond portfolio. For retirements longer than 30 years, 3-3.5% is recommended.

What is sequence-of-returns risk in retirement?+

Sequence risk is the danger that a market downturn early in retirement permanently depletes your portfolio. Withdrawing from a declining portfolio locks in losses and reduces the capital available to recover. Mitigation strategies include cash buffers, flexible spending, and a bond floor for near-term withdrawals.

How do Required Minimum Distributions (RMDs) work?+

The IRS requires withdrawals from Traditional IRAs and 401ks starting at age 73 (SECURE 2.0 Act). The annual RMD equals your account balance divided by an IRS life expectancy factor. Failing to take the RMD triggers a 25% penalty. Roth IRAs have no RMDs during the owner's lifetime.

Should I withdraw from taxable, tax-deferred, or Roth accounts first?+

The conventional order: taxable accounts first (capital gains taxed favorably), then tax-deferred (Traditional IRA/401k), Roth last (tax-free growth preserved longest). Strategic Roth conversions during low-income early retirement years can reduce lifetime tax significantly.

🔗 Related Calculators

How long will $1 million last in retirement?

At a 4% annual withdrawal ($40,000/year or $3,333/month) with a 5% annual return: $1 million will last indefinitely (the return exceeds withdrawals). At zero return, $1 million lasts 25 years at $40,000/year. At a 6% withdrawal ($60,000/year) with 5% return: approximately 28 years. The key is the relationship between the withdrawal rate and the portfolio return.

What is the 4% rule?

The 4% rule, from William Bengen's 1994 research, states that you can withdraw 4% of your initial portfolio in year 1, then adjust for inflation annually, and the portfolio will last at least 30 years with high probability. Based on a 50/50 stock/bond portfolio and historical US market data, this rule survived all 30-year historical periods from 1926 to the present, including the Great Depression and 1970s inflation.

What withdrawal rate is safe for early retirement?

For a 30-year retirement (retiring at 65 with 95 life expectancy), 4% is the widely cited safe rate. For a 40-year retirement (retiring at 55), 3.5% is more conservative. For a 50-year retirement (retiring at 45, FIRE), 3–3.25% is often recommended. The longer the retirement horizon, the more sequence-of-returns risk there is - a market crash early in retirement can permanently impair a portfolio's longevity.

How do I calculate a sustainable monthly withdrawal?

Sustainable monthly withdrawal = Portfolio Balance × Annual SWR / 12. For a $800,000 portfolio at 4% SWR: $800,000 × 4% / 12 = $2,667/month. This keeps the real purchasing power of the portfolio intact over 30 years in most historical scenarios. Adjust upward with a higher return rate or shorter retirement horizon.

What is the 4% safe withdrawal rule?

How do I adjust withdrawals for inflation?

What portfolio return should I assume in retirement?

How long should I plan for my retirement corpus to last?

📌 Quick Tips

💡The 4% rule (withdrawing 4% of the initial portfolio annually) has historically sustained a 30-year retirement in nearly all market conditions.

💡For a 40+ year retirement (early retirees), a 3–3.5% withdrawal rate provides a higher probability of not depleting the portfolio.

💡A 1% lower withdrawal rate significantly extends portfolio longevity - the difference between 4% and 3% can add 10–15 years.

💡The FAQ section below answers the most common questions about this topic.

💡Results are rounded to a practical number of decimal places for everyday use.