Coast FIRE represents one of the most psychologically liberating approaches to financial independence. By front-loading your retirement savings in your 20s and 30s, you can reach a point where your investments will grow to full FIRE without another dollar saved. This comprehensive guide breaks down everything you need to know about Coast FIRE, from the mathematical foundations to real-world implementation strategies.
Unlike traditional FIRE where you save until you have 25x your annual expenses, Coast FIRE lets you "coast" once you've saved enough that compound interest will carry you to retirement. This means potentially decades of work where every dollar earned can be spent guilt-free, pursuing passions without financial pressure, and living life on your terms starting in your 30s or 40s.
Quick Coast FIRE Calculator
Your Coast FIRE Projection
Understanding Coast FIRE: The Mathematics
Coast FIRE is built on the power of compound interest and time. The concept is elegantly simple: save aggressively early, then let time and market returns do the heavy lifting. Here's the fundamental formula that makes it all work:
The Coast FIRE Formula
Coast FIRE Number = Traditional FIRE Number ÷ (1 + Return Rate)^Years Until RetirementWhere:
- • Traditional FIRE Number = Annual Expenses × 25
- • Return Rate = Expected annual investment return (typically 7%)
- • Years Until Retirement = Target retirement age - Current age
* Assuming $70,000 annual expenses in retirement ($1.75M traditional FIRE number)
The Power of Time: Coast Numbers by Age
The earlier you start, the less you need. Starting at 25 requires only 13% of the traditional FIRE number!
The Three Phases of Coast FIRE
Phase 1: Aggressive Accumulation
Years 0-10: Save 50-70% of income, maximize all tax-advantaged accounts, live below your means
Focus Areas:
- • Maximize 401(k) contributions
- • Max out IRA (Roth or Traditional)
- • Contribute to HSA if available
- • Build taxable investment accounts
Lifestyle:
- • House hack or rent cheaply
- • Drive used cars or bike
- • Cook meals at home
- • Find free entertainment
Phase 2: The Coast Period
Years 10-30: Work only to cover expenses, pursue passion projects, complete geographic flexibility
Work Options:
- • Part-time employment
- • Freelancing/consulting
- • Passion business
- • Seasonal work + travel
Freedom Gained:
- • No savings pressure
- • Location independence
- • Career experimentation
- • Extended time off
Phase 3: Traditional Retirement
Age 60-65+: Access retirement accounts, begin 4% withdrawals, complete financial independence
Portfolio Status:
- • $2-4M+ portfolio value
- • 4% safe withdrawal rate
- • Tax-efficient withdrawals
- • Legacy planning options
Lifestyle:
- • Complete freedom
- • Travel extensively
- • Pursue hobbies fully
- • Volunteer/give back
Accumulation Phase: Building Your Coast Number
Savings Trajectory Comparison
Higher savings rates dramatically reduce time to Coast FIRE. The difference between 30% and 70% can be 10+ years.
Income Optimization
Negotiate Salary
Every $10K increase = 2 years faster
Side Hustles
$1K/month extra = 30% faster
Job Hopping
20% raises every 2-3 years
Expense Reduction
House Hacking
Save $1,500+/month on housing
Car-Free Living
Save $600+/month total cost
Meal Prep
Save $400+/month vs eating out
The Coasting Phase: Living Your Best Life
Once you hit your Coast FIRE number, the entire game changes. You no longer need to save for retirement—you just need to cover your current expenses. This opens up incredible lifestyle options that would be impossible while pursuing traditional FIRE.
Portfolio Growth During Coasting
Starting with $500K at 35, your portfolio grows to $3.8M by 65 without adding a single dollar!
Income Options During Coasting
| Income Source | Annual Income | Hours/Week | Pros | Best For |
|---|---|---|---|---|
| Freelance Consulting | $40-80K | 10-20 | High hourly rate, flexible | Professionals |
| Online Business | $20-100K+ | 15-30 | Location independent | Digital nomads |
| Teaching/Tutoring | $30-50K | 20-30 | Rewarding, summers off | Educators |
| Real Estate (1-2 properties) | $20-40K | 5-10 | Mostly passive | Property owners |
| Seasonal Work | $25-35K | 40 (3-6 months) | Long breaks | Travel lovers |
Lifestyle Benefits of Coasting
Mental Health
- • Zero financial stress
- • Work becomes optional
- • Pursue passions freely
- • No retirement anxiety
Freedom
- • Location independence
- • Time flexibility
- • Career experimentation
- • Extended travel possible
Relationships
- • More family time
- • Deeper friendships
- • Community involvement
- • Better work-life balance
Geographic Arbitrage: Accelerate Your Coast
One of the most powerful Coast FIRE strategies is geographic arbitrage—earning in high-income areas while living in low-cost areas, or moving to cheaper locations once you start coasting.
Income vs Expenses by Location
Domestic Arbitrage
High Income → Low Cost
Work remotely for SF/NYC companies while living in LCOL areas
- • Austin, TX: No state income tax
- • Raleigh, NC: 40% cheaper than SF
- • Salt Lake City: Outdoor paradise
International Options
Popular Coast Destinations
Live like royalty on $2K/month while portfolio grows
- • Portugal: Golden visa program
- • Thailand: Digital nomad visa
- • Mexico: Close to US, great weather
Coast FIRE by Age: Real Scenarios
Your age when starting significantly impacts your Coast FIRE journey. Here are three detailed scenarios showing how the path differs based on when you begin.
Early Starter
Starting at age 22
$4,200,000
at age 65
Typical Professional
Starting at age 28
$3,500,000
at age 65
Late Bloomer
Starting at age 35
$3,000,000
at age 65
Key Takeaways
- Starting 5 years earlier can reduce required savings by 40-50%
- Late starters need higher savings rates but can still achieve Coast FIRE
- Every year of delay increases the required Coast number by ~7-10%
Common Coast FIRE Mistakes to Avoid
Mistake #1: Forgetting About Healthcare
Many Coast FIRE planners forget they'll need health insurance for 20-30 years before Medicare.
Solution:
- • Budget $500-1,500/month for ACA marketplace plans
- • Consider part-time work with benefits
- • Research healthcare sharing ministries
- • Plan for geographic arbitrage to countries with affordable healthcare
Mistake #2: Using Overly Optimistic Returns
Assuming 10-12% returns can leave you severely underfunded.
Solution:
- • Use 6-7% real returns for planning
- • Build in a 20% buffer to your Coast number
- • Consider different market scenarios
- • Review and adjust annually
Mistake #3: Lifestyle Inflation During Coasting
Increasing expenses during the coast phase can derail your plan.
Solution:
- • Lock in your expense baseline before coasting
- • Track spending monthly during coast phase
- • Build raises into fun money, not baseline
- • Review your original FIRE number annually
Mistake #4: Not Accounting for Inflation
$70K expenses today will be $140K+ in 30 years with 2.5% inflation.
Solution:
- • Use inflation-adjusted (real) returns in calculations
- • Plan for expense growth during coasting
- • Consider TIPS or I Bonds for inflation protection
- • Build flexibility into your retirement date
Your Coast FIRE Implementation Checklist
Phase 1: Preparation (Month 1-3)
Phase 2: Accumulation (Years 1-10)
Phase 3: Transition to Coasting
Start Your Coast FIRE Journey Today
Your Next Steps
Immediate Actions (This Week)
- 1
Calculate your Coast number
Use our detailed Coast FIRE Calculator → - 2
Track current expenses
Download Mint, YNAB, or use spreadsheets
- 3
Review investment accounts
Ensure you're maximizing tax advantages
30-Day Goals
- 1
Increase 401(k) contribution
Bump up by 5-10% immediately
- 2
Find one expense to cut
Cancel subscriptions, negotiate bills
- 3
Research coast careers
Identify passion work that covers expenses
Ready to calculate your exact Coast FIRE timeline?
Final Thoughts
Coast FIRE offers something unique in the financial independence world: the ability to completely decouple saving from living. By front-loading your retirement savings, you buy yourself decades of freedom to pursue work you love, travel extensively, raise a family without financial stress, or simply enjoy life without the constant pressure to save.
The math is compelling—someone who saves aggressively from 25-35 can coast for the next 30 years, watching their portfolio grow from $500,000 to over $3 million without adding another penny. This isn't about being lazy or giving up on ambition; it's about strategically timing your efforts to maximize both wealth and life enjoyment.
Whether you're 22 or 42, Coast FIRE is achievable with the right strategy and commitment. The key is to start now, save aggressively during your peak earning years, and trust in the mathematical certainty of compound interest. Your future self—the one working part-time at a beach cafe or teaching yoga in Bali while your portfolio grows—will thank you.
Remember: Coast FIRE isn't about retiring completely. It's about reaching a point where retirement is inevitable, giving you the freedom to make choices based on passion rather than paycheck. Start calculating your Coast number today, and take the first step toward a life of financial freedom and purposeful work.