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Partner 2
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Your Coast FIRE Results
Understanding Your Couples Coast FIRE Results
Combined vs Individual Mode Results
Combined mode gives you one household Coast FIRE number, treating you as a single financial unit. This is simpler and works well for same-age couples retiring together. Individual mode shows separate Coast FIRE numbers for each partner, revealing each person's contribution. Use Individual mode when you have age differences, different retirement ages, or want to understand each partner's financial responsibility. Both modes are mathematically sound—choose based on your planning preferences.
What Your Numbers Mean
Your Coast FIRE number is the savings milestone where you can stop contributing to retirement and let compound interest do the rest. If you've reached your number, congratulations—you've secured retirement! If you're short, the calculator shows exactly how much more you need. This gap is your immediate savings target. Once you hit Coast FIRE, you gain incredible flexibility: take lower-paying jobs, work part-time, start a business, or pursue passion projects without worrying about retirement.
Handling Age and Retirement Differences
Age gaps and different retirement timelines significantly impact Coast FIRE numbers. The younger partner typically needs less saved today because their money has more time to grow. The older partner or earlier retiree needs more. If one partner retires early while the other works, consider whether the working partner's income will cover household expenses during the gap years. This affects your Coast FIRE calculations and overall retirement strategy.
Creating Your Joint Action Plan
Use your Coast FIRE numbers to create a concrete savings plan. If you're short of your target, calculate monthly savings needed: divide the shortfall by months until you want to reach Coast FIRE. For example, a $50,000 gap over 5 years requires $833/month. Decide together how to split savings contributions—proportional to income, equal amounts, or another arrangement. Review your Coast FIRE progress annually and adjust as circumstances change.
What is Coast FIRE for Couples?
Real-World Couples Coast FIRE Examples
See how different couples calculate their Coast FIRE numbers based on their unique situations.
Example 1: Same-Age Couple, Dual Income, Joint Retirement
Sarah (32, software engineer earning $90,000) and Mike (32, high school teacher earning $55,000) live in Denver, Colorado. Married for 3 years with no children yet, they both work full-time and plan to retire together at 65. They have $150,000 saved and expect to spend $60,000 annually in retirement.
Calculation Steps
- Partner 1 (Sarah): Age 32
- Partner 2 (Mike): Age 32
- Current Savings: $150,000
- Annual Retirement Expenses: $60,000
- Both Retirement Ages: 65 (33 years away)
- Calculation Mode: Combined Household
- Investment Return: 7% annually
- Withdrawal Rate: 4% (safe withdrawal rule)
- Retirement Corpus Needed: $60,000 ÷ 0.04 = $1,500,000
- Years to Retirement: 65 - 32 = 33 years
- Coast FIRE Number: $1,500,000 ÷ (1.07)^33 = $164,438
Example 2: Age Gap Couple, Different Retirement Ages
Jennifer (40, healthcare administrator earning $85,000) and David (32, graphic designer earning $65,000) met later in life and married 2 years ago. Living in Portland, Oregon, Jennifer plans to retire at 60 to pursue travel, while David will continue working until 65. They have $200,000 saved and need $70,000 annually in retirement.
Calculation Steps
- Partner 1 (Jennifer): Age 40, retiring at 60 (20 years)
- Partner 2 (David): Age 32, retiring at 65 (33 years)
- Current Savings: $200,000
- Annual Retirement Expenses: $70,000
- Calculation Mode: Individual (different retirement ages)
- Expense Share: 50% each
- Jennifer's Target: ($70,000 × 50%) ÷ 0.04 = $875,000
- Jennifer's Coast FIRE: $875,000 ÷ (1.07)^20 = $226,149
- David's Target: ($70,000 × 50%) ÷ 0.04 = $875,000
- David's Coast FIRE: $875,000 ÷ (1.07)^33 = $95,925
- Total Household Coast FIRE: $226,149 + $95,925 = $322,074
Example 3: Single-Income Family, One Partner at Home
Alex (35, mechanical engineer earning $95,000) works full-time while Jordan (33, former teacher) stays home with their two young children in suburban Atlanta. They made the decision for Jordan to leave teaching to focus on childcare and homeschooling. They have $120,000 saved and plan to spend $55,000 annually in retirement, both retiring at 65.
Calculation Steps
- Partner 1 (Alex): Age 35, working
- Partner 2 (Jordan): Age 33, stay-at-home parent
- Current Savings: $120,000
- Annual Retirement Expenses: $55,000
- Both Retirement Ages: 65
- Calculation Mode: Individual
- Alex's Expense Share: 100% (sole earner)
- Jordan's Expense Share: 0%
- Alex's Target: ($55,000 × 100%) ÷ 0.04 = $1,375,000
- Alex's Years to Retirement: 65 - 35 = 30 years
- Alex's Coast FIRE: $1,375,000 ÷ (1.07)^30 = $180,491
- Jordan's Coast FIRE: $0 (0% expense share)
- Total Household Coast FIRE: $180,491
How to Use the Couples Calculator
Follow these six simple steps to calculate your joint Coast FIRE number.
Select Calculation Mode
Choose between Combined Household mode (treats you as one financial unit) or Individual mode (calculates separate Coast FIRE numbers for each partner). Combined mode is simpler and works well for couples with similar ages and retirement plans. Individual mode offers more flexibility for age differences and different retirement timelines.
Enter Both Partners' Ages
Input the current age for both Partner 1 and Partner 2. Age differences are automatically accounted for in the calculations. The calculator uses the older partner's age as the baseline for combined mode, ensuring conservative estimates. Don't worry about who is Partner 1 or 2—the math works the same.
Input Current Household Savings
Enter your total combined savings and investments that will grow toward retirement. Include 401(k)s, IRAs, taxable investment accounts, and other retirement savings. Don't include your home equity or emergency fund unless you plan to use them for retirement. This is your starting point for Coast FIRE calculations.
Set Annual Retirement Expenses
Estimate how much you'll spend annually in retirement as a household. Include housing, food, healthcare, travel, and leisure activities. Use your current spending as a baseline, adjusting for changes like paid-off mortgages or increased healthcare costs. This determines your required retirement corpus.
Choose Retirement Ages
Set the target retirement age for each partner. You can retire at the same age or different ages—the calculator handles both scenarios. Earlier retirement requires higher Coast FIRE numbers today. Consider career satisfaction, health, and financial goals when choosing retirement ages for each partner.
Adjust Expense Sharing (Individual Mode)
If using Individual mode, set what percentage of retirement expenses each partner will cover. Default is 50/50, but you can adjust based on income ratios, personal preferences, or family arrangements. For single-income families, set one partner to 100% and the other to 0%. The calculator ensures percentages total 100%.
Why Use Our Couples Calculator?
Specialized features designed for couples planning Coast FIRE together.
Dual Calculation Modes
Choose between combined household mode for unified planning or individual mode to see each partner's separate Coast FIRE numbers. Switch modes instantly to compare different approaches and find what works best for your relationship and financial goals.
Age Difference Support
Accurately handles age gaps between partners, whether you're the same age or years apart. The calculator adjusts for different retirement timelines and compound growth periods, ensuring realistic Coast FIRE targets for both partners regardless of age difference.
Flexible Expense Allocation
Customize how retirement expenses are split between partners. Set equal 50/50 sharing, proportional to income, or any custom ratio that reflects your financial arrangement. Perfect for traditional, modern, or unique partnership structures.
Single-Income Family Friendly
Works perfectly for families where one partner works while the other manages the home. Allocate 100% of expenses to the working partner or split based on your preferred model. Recognizes that financial contributions come in many forms.
Understanding the Parameters
Learn what each input means and how it affects your Coast FIRE calculations.
Partner 1 Age
Current age of the first partner, ranging from 18 to 80 years old. This determines how many years their savings have to grow through compound interest before retirement. Younger ages result in lower Coast FIRE numbers due to more growth time.
Partner 2 Age
Current age of the second partner. Can be the same as Partner 1 or different. Age differences are automatically handled in calculations. The calculator uses appropriate compound growth periods for each partner based on their individual ages and retirement timelines.
Current Household Savings
Total combined savings and investments for both partners. Include all retirement accounts, investment portfolios, and savings earmarked for retirement. This is your starting principal that will grow to your Coast FIRE target through compound interest over time.
Annual Retirement Expenses
Expected yearly spending during retirement for your household. Cover all costs: housing, utilities, food, healthcare, insurance, travel, hobbies, and miscellaneous expenses. Be realistic—underestimating leads to insufficient retirement funds. Adjust for inflation if using the advanced options.
Partner 1 Retirement Age
Age when Partner 1 plans to retire and begin drawing from retirement savings. Must be greater than current age. Traditional retirement is 65, but you can choose earlier or later based on career goals, health, and financial readiness.
Partner 2 Retirement Age
Age when Partner 2 plans to retire. Can match Partner 1's retirement age or differ. Different retirement ages are common—one partner may retire early while the other continues working. The calculator handles staggered retirements accurately.
Calculation Mode
Choose Combined Household (treats you as one unit with shared retirement corpus) or Individual (calculates separate Coast FIRE numbers for each partner). Combined is simpler; Individual offers more detailed insights into each partner's contribution and is better for age differences.
Partner 1 Expense Share
Percentage of annual retirement expenses Partner 1 will cover (Individual mode only). Default is 50%, but adjust based on income ratios, agreements, or family structure. For single-income families, set to 100% for the working partner. Must total 100% with Partner 2's share.
Partner 2 Expense Share
Percentage of annual retirement expenses Partner 2 will cover (Individual mode only). Automatically adjusts to ensure total is 100% with Partner 1. Set to 0% if Partner 2 is a stay-at-home partner in a single-income household scenario.
Annual Return Rate
Expected yearly investment return before retirement. Default 7% represents conservative historical stock market averages. Higher returns mean lower Coast FIRE numbers today, but be realistic about market volatility and your risk tolerance. Adjust in advanced settings.
The Couples Coast FIRE Calculation Formula
Understanding the math behind your joint Coast FIRE number helps you make informed decisions.
Combined Household Mode Formula
In Combined mode, we treat you as one financial unit. First, calculate the total retirement corpus needed using the 4% safe withdrawal rule. Then, discount it to present value using the older partner's timeline (more conservative). For example, if you need $50,000 annually with a 4% withdrawal rate, you need $1,250,000 at retirement. If the older partner has 35 years until retirement at 7% returns, your Coast FIRE number today is $117,588.
Retirement Corpus = Annual Expenses ÷ Withdrawal Rate; Coast FIRE = Corpus ÷ (1 + Return)^Years
Example: Partners aged 30 & 28, retiring at 65, needing $50,000/year: Corpus = $50,000 ÷ 0.04 = $1,250,000; Coast FIRE = $1,250,000 ÷ (1.07)^35 = $117,588
Individual Mode Formula
In Individual mode, each partner gets their own Coast FIRE calculation based on their expense share and timeline. Partner 1 covering 60% of $50,000 expenses needs $750,000 at retirement. With 30 years to grow at 7%, their Coast FIRE number is $98,540. Partner 2 covering 40% needs $500,000, which discounts to $65,694 over 35 years. Total household Coast FIRE is the sum: $164,234.
Each Partner: Personal Corpus = (Annual Expenses × Share) ÷ Withdrawal Rate; Personal Coast FIRE = Corpus ÷ (1 + Return)^Personal Years
Example: Partner 1 (35 years old, 60% share, 25 years to retire): $750,000 ÷ (1.07)^25 = $138,187; Partner 2 (30 years old, 40% share, 35 years): $500,000 ÷ (1.07)^35 = $47,035; Total = $185,222
Frequently Asked Questions
Get answers to common questions about Coast FIRE planning for couples.
It depends on your situation. Use Combined mode if you're similar ages, plan to retire together, and view finances as fully shared. This gives one simple target. Use Individual mode if you have age differences, different retirement timelines, or want to understand each partner's contribution. Individual mode is also better for couples who maintain some financial independence. Both approaches are valid—choose what fits your relationship and planning style.
Different retirement ages are completely normal and our calculator handles them perfectly. Use Individual mode and set each partner's retirement age separately. The calculator will compute appropriate Coast FIRE numbers based on each person's timeline. The earlier retiree will need more saved today (less time for growth), while the later retiree needs less. Consider whether the working partner's income will cover household expenses during the gap years between retirements.
Single-income families work great with our calculator. Use Individual mode and set the working partner's expense share to 100% and the stay-at-home partner to 0%. This allocates all Coast FIRE savings to the working partner while recognizing the stay-at-home partner's invaluable non-financial contributions. The calculator will show the working partner's required Coast FIRE number to support the entire household in retirement. This model respects that financial contributions aren't the only valuable contributions to a partnership.
There's no one right answer—it depends on your values and circumstances. Common approaches: (1) 50/50 split for equal partnership, (2) proportional to income (if one earns 60%, they cover 60%), (3) 100/0 for single-income families, (4) custom ratios based on agreements or family structure. The calculator supports any split as long as it totals 100%. Discuss with your partner and choose what feels fair and sustainable for your relationship.
This is a common scenario and perfectly manageable. Use Individual mode with different retirement ages. The early retiree will need a higher Coast FIRE number today because they have less time for compound growth. Important consideration: will the working partner's income cover household expenses during the gap years? If yes, the early retiree only needs to cover their own retirement expenses. If no, you'll need additional savings to bridge the gap. Plan carefully for this transition period.
For current expenses while kids are home, yes—include them in your annual spending. For retirement expenses, typically no—most people's kids are independent adults by retirement. However, if you plan to support adult children or grandchildren in retirement, include those costs in your annual retirement expenses. Also consider that your expenses may decrease significantly once kids are independent (no college costs, smaller home, etc.), so adjust your retirement spending estimate accordingly.
This is a personal decision that doesn't affect Coast FIRE calculations. Whether you have joint accounts, separate accounts, or a mix, what matters is your total household savings. The calculator uses combined savings regardless of how accounts are structured. Some couples prefer joint accounts for simplicity and unity; others maintain separate accounts for independence and clarity. Choose what works for your relationship, but track total household savings for Coast FIRE purposes.