How Long Will My Money Last Calculator

Estimate how many years your savings will last based on your withdrawal rate, investment returns, and inflation

Comprehensive Guide: How Long Will My Money Last in Retirement?

Planning for retirement requires careful consideration of how long your savings will last. This comprehensive guide explains the key factors that determine your money’s longevity and provides actionable strategies to maximize your financial security.

Understanding the Core Principles

The “how long will my money last” calculation depends on four primary factors:

1. Initial Savings: Your starting balance when you begin withdrawals
2. Withdrawal Rate: How much you take out annually (typically 3-5% is considered safe)
3. Investment Returns: The growth rate of your remaining balance
4. Inflation: The rising cost of goods that erodes purchasing power

The 4% Rule: A Starting Point

The 4% rule, developed by financial planner William Bengen in 1994, suggests that retirees can safely withdraw 4% of their portfolio in the first year of retirement, then adjust that amount for inflation each subsequent year. Historical data shows this approach provides a high probability (95%+) that savings will last 30 years.

Trinity Study Findings

The original Trinity Study (1998) from three professors at Trinity University analyzed withdrawal rates from 1926-1995 and found that 4% was sustainable for 30-year periods in nearly all scenarios.

Source: American Association of Individual Investors

How Investment Returns Affect Longevity

Your portfolio’s growth rate dramatically impacts how long your money lasts. Consider these scenarios with $500,000 initial savings and $20,000 annual withdrawals:

Annual Return	Years Money Lasts	Final Balance
3%	31 years	$0
5%	42 years	$128,456
7%	Infinite (grows indefinitely)	Grows over time

Note: These calculations assume 2.5% annual inflation with inflation-adjusted withdrawals.

The Impact of Inflation on Your Savings

Inflation silently erodes your purchasing power. What costs $20,000 today will cost $26,286 in 10 years at 2.5% inflation. Our calculator accounts for this by:

• Adjusting your withdrawal amount annually to maintain purchasing power
• Reducing the real value of your investment returns
• Showing how inflation compounds over time

U.S. Bureau of Labor Statistics Data

The average annual inflation rate in the U.S. from 1960-2023 was 3.8%. The Consumer Price Index shows how prices have changed for common goods and services over time.

Source: U.S. Bureau of Labor Statistics

Withdrawal Strategies to Extend Your Savings

Consider these advanced strategies to make your money last longer:

1. Dynamic Withdrawal Rates: Adjust your withdrawal percentage based on portfolio performance (e.g., 4% when up, 3% when down)
2. Bucket Strategy: Segment your savings into short-term (cash), medium-term (bonds), and long-term (stocks) buckets
3. Annuity Laddering: Purchase annuities at different ages to create guaranteed income streams
4. Tax Efficiency: Withdraw from taxable, tax-deferred, and tax-free accounts in the optimal order
5. Part-Time Work: Even modest income can significantly reduce withdrawal needs

Common Mistakes to Avoid

Avoid these pitfalls that can prematurely deplete your savings:

• Overestimating Returns: Assuming 8-10% returns when 5-7% is more realistic for balanced portfolios
• Underestimating Expenses: Healthcare costs often rise faster than general inflation
• Ignoring Sequence Risk: Poor returns in early retirement years can devastate longevity
• No Emergency Fund: Unexpected expenses force larger-than-planned withdrawals
• No Flexibility: Refusing to adjust spending during market downturns

How to Use Our Calculator Effectively

For most accurate results:

1. Start with your current retirement savings balance
2. Enter your planned annual spending (not including Social Security/pensions)
3. Use conservative return estimates (5-6% for balanced portfolios)
4. Use the long-term average inflation rate (2.5-3%)
5. Run multiple scenarios with different assumptions
6. Consider creating a “worst-case” scenario with low returns and high inflation

Real-World Example Calculations

Let’s examine three different retirees with $600,000 saved:

Retiree	Annual Spending	Portfolio Return	Inflation	Years Money Lasts
Conservative Sarah	$24,000 (4%)	4%	2%	35 years
Moderate Mike	$30,000 (5%)	5%	2.5%	28 years
Aggressive Alex	$36,000 (6%)	6%	3%	22 years

Note: All examples assume annual inflation adjustments to withdrawals.

When to Consult a Financial Professional

While our calculator provides valuable estimates, consider professional advice if:

• You have complex assets (business interests, rental properties, etc.)
• Your tax situation is complicated
• You’re considering early retirement (before age 59½)
• You have significant debt
• You want to create a comprehensive estate plan

CFP Board Resources

The Certified Financial Planner Board of Standards provides tools to find qualified professionals who can help with retirement planning, tax strategies, and investment management.

Source: CFP Board

Final Thoughts: Making Your Money Last

The key to retirement security lies in:

1. Starting with realistic assumptions about returns and inflation
2. Maintaining flexibility in your spending
3. Regularly reviewing and adjusting your plan
4. Considering guaranteed income sources (Social Security optimization, annuities)
5. Having a backup plan for unexpected expenses or market downturns

Use this calculator as a starting point, but remember that real-life retirement planning requires ongoing attention and adjustment. The most successful retirees are those who monitor their finances regularly and are willing to adapt their strategies as needed.