What is Coast FIRE?
Discover the FIRE milestone that lets you stop aggressive saving decades earlier. Learn how Coast FIRE works and calculate your number.
The Basics of Coast FIRE
Coast FIRE (also called Coast FI) represents a fundamental shift in how we think about financial independence. Rather than grinding for decades to hit a massive number, you front-load your savings early in life, then let compound growth do the heavy lifting while you shift your focus from wealth accumulation to simply covering expenses.
The Core Concept
Save aggressively in your 20s and 30s to hit a target amount, then take your foot off the gas. Your nest egg grows on autopilot while you work just enough to pay the bills—no more maxing out retirement accounts or living on rice and beans.
The term "coast" perfectly captures the feeling: you've done the hard work of climbing the hill, and now you can coast downhill to your destination. This appeals to people who've grown disillusioned with the traditional FIRE grind—years of extreme frugality, constant spreadsheet optimization, and feeling like life is on pause until you hit "the number."
Coast FIRE has gained significant traction in recent years, particularly among millennials who watched their parents work gruelling jobs for decades. The concept emerged from online FIRE communities around 2017-2018 as people began questioning whether extreme frugality for 15+ years was really the only path to financial security.
Want to calculate your own Coast FIRE number?
Try Our Coast FIRE CalculatorCoast FIRE vs Traditional FIRE
Understanding the difference between Coast FIRE and traditional FIRE is essential for choosing the right path for your situation.
The Power of Time
The earlier you start, the lower your Coast FIRE number. At 25, you might only need $75,000 to coast to $1,000,000 at 65. At 40, you'd need closer to $260,000. Time is your greatest asset with Coast FIRE.
How to Calculate Your Coast FIRE Number
Step 1: Determine Your FIRE Number
Calculate 25x your desired annual retirement income. This is your full FIRE number using the 4% rule.
Step 2: Estimate Your Expected Return
A diversified stock portfolio has historically returned about 7% after inflation. Be conservative in your estimates.
Step 3: Calculate Years to Retirement
Subtract your current age from your target retirement age (typically 60-67).
Step 4: Apply the Formula
Divide your FIRE number by (1 + return rate) raised to the power of years until retirement.
The Coast FIRE Formula
Coast FIRE Number = FIRE Number ÷ (1 + return rate)years
Example: $1,000,000 ÷ (1.07)30 = $131,000
Example: 35-Year-Old Targeting 65
Benefits of Coast FIRE
Achievable Milestone
Coast FIRE is often reachable in your 30s or early 40s, while full FIRE might take until your 50s. It's a tangible goal that feels attainable.
Career Flexibility
Once you've "coasted," you can take a lower-paying job you love, go part-time, or start a business without risking your retirement.
Reduced Pressure
No more feeling like every dollar must go to savings. You've already secured your future, so you can enjoy life now.
Better Work-Life Balance
You can prioritize family, hobbies, and experiences instead of maximizing income at all costs.
What You Can Do After Reaching Coast FIRE
- Switch to a passion career that pays less but brings more fulfillment
- Work part-time or take extended breaks between jobs
- Start a business without the pressure of it "needing" to work
- Take a sabbatical to travel, learn, or spend time with family
- Volunteer or do meaningful work without worrying about income
- Move to a lower cost-of-living area and work remotely
The Real Risks Nobody Talks About
Coast FIRE has its critics. Some traditional FIRE purists dismiss it as "lazy man's FI" because you still have to work. But the real concerns go deeper than that. Here's what you need to genuinely worry about:
Sequence of Returns Risk During Coasting
This risk is usually discussed for retirement withdrawals, but it matters just as much for Coast FIRE. A severe market crash early in your coasting period—when you're no longer contributing—can devastate your timeline. Without new contributions to "average down" during corrections, a bad sequence of returns may force you to resume saving or delay retirement by years. Many financial planners suggest building a 10-15% buffer above your Coast number specifically for this risk.
Inflation Uncertainty
The calculation assumes inflation stays predictable. Periods of unexpectedly high inflation (like 2022-2023) can erode purchasing power faster than the formula captures. If your Coast number is $131,000 at 7% returns,many planners recommend targeting $150,000 before truly coasting.
The Motivation Problem
Some people find it difficult to maintain direction once aggressive saving pressure is removed. The shift from "wealth-building mode" to "expense-covering mode" requires a different mindset—and not everyone makes that transition smoothly. You may feel aimless without a financial goal to pursue.
Future Expense Guesswork
Your retirement spending estimate is a guess about life decades from now. Healthcare costs, housing situations, family needs, eldercare responsibilities—these shift in ways that are impossible to predict. A comfortable $40,000/year today might feel tight at 65.
Career Re-entry Risk
If you downshift to part-time or passion work, returning to high-paying employment later becomes harder. Skills atrophy, networks fade, and age discrimination is real. Make sure you're truly comfortable with the trade-off.
Mitigation Strategies
- Use conservative return estimates (5-6% real return instead of 7%)
- Build a 10-15% buffer above your calculated Coast number
- Keep a small cash reserve for market downturns
- Stay flexible with your retirement age—be willing to adjust
- Consider making small contributions during major market crashes
- Don't factor in Social Security—treat it as a bonus if it exists
The Psychology of Coasting
Perhaps the most overlooked aspect of Coast FIRE is the psychological shift it requires. Many people inonline communitiesreport that the hardest part isn't the math—it's changing your relationship with money and work.
The Permission Problem
After years of aggressive saving, many people struggle to give themselves permission to stop. They hit their Coast number but keep grinding anyway, unable to break the habit. The identity of being a "saver" becomes harder to shed than expected.
Purpose Beyond the Number
FIRE gives you a clear goal and dopamine hit with every milestone. Coast FIRE removes that structure. You need to find new sources of meaning and progress, or the freedom can feel empty. Have a plan for what you'll do with your reclaimed time and energy.
A Cautionary Tale
A common story in FIRE communities: someone spends five years saving aggressively, stops socialising due to costs, hasn't travelled, and feels like they're "waiting for life to start." Coast FIRE was created partly as a response to this—a recognition that the journey matters, not just the destination. As The Coast FI Guy puts it: "Coasting to financial independence is a conscious decision to delay your FI date in exchange for freedom and flexibility now."
Coast FIRE Communities & Resources
Coast FIRE has a growing community of practitioners sharing experiences, strategies, and support. Here are the best places to learn more:
Frequently Asked Questions
What is Coast FIRE?
Coast FIRE is a financial milestone where you have enough invested that compound growth alone will reach your full retirement number by traditional retirement age. Once you hit Coast FIRE, you only need to earn enough to cover current expenses—no more aggressive saving required.
How is Coast FIRE different from regular FIRE?
Traditional FIRE requires saving enough to retire immediately (typically 25x annual expenses). Coast FIRE requires a much smaller amount today that will grow to your FIRE number by retirement age. Coast FIRE is often achievable 10-20 years earlier than full FIRE.
How do I calculate my Coast FIRE number?
Divide your FIRE number by (1 + expected return)^years until retirement. For example, if you need 1 million at 65, expect 7% returns, and you're 30 (35 years away), your Coast FIRE number is about 94,000.
What can I do after reaching Coast FIRE?
After reaching Coast FIRE, you can take a lower-paying job you love, work part-time, start a business, take sabbaticals, or pursue passion projects. You only need to earn enough to cover your current living expenses.
What return rate should I assume?
A diversified stock portfolio has historically returned about 10% nominally or 7% after inflation. For conservative planning, consider using 5-6% to account for potential lower future returns or higher inflation.
Should I stop saving completely after reaching Coast FIRE?
You don't have to, but you could. Many people continue saving a small amount for extra security or to reach full FIRE earlier. The key is that you no longer need to save aggressively.
What about inflation?
Inflation erodes purchasing power over time. Use "real returns" (nominal return minus inflation) in your calculations. Our Coast FIRE calculator has an option to adjust for inflation automatically.
Is Coast FIRE right for me?
Coast FIRE is ideal if you want financial security without extreme frugality, value work-life balance over early retirement, want career flexibility, or find the full FIRE target too daunting. It's a middle ground between aggressive FIRE and traditional retirement.
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