What Is Coast FIRE? The Strategy That Lets You Stop Saving and Still Retire Early
Most conversations about early retirement focus on accumulation — save more, invest more, reach the number faster. Coast FIRE flips that script entirely. The core idea is simple: if you've already saved enough, compound growth will do the rest of the work for you. You can stop making retirement contributions, let the money grow untouched, and spend your current income on your life — not your future.
For many people, Coast FIRE turns out to be closer than they realized. If you've been investing consistently since your 20s or early 30s, there's a real chance you've already crossed the threshold.
The Coast FIRE Definition
You've reached Coast FIRE when your current investment portfolio is large enough that — assuming a reasonable long-term growth rate and without any additional contributions — it will compound to your full FIRE number by your target retirement age.
In other words: you can stop rowing and just coast to the finish line.
This is meaningfully different from full FIRE, where you've accumulated enough to retire immediately. With Coast FIRE, you still need income to cover your living expenses — you're just no longer required to save and invest any of it for the future. Your job shifts from "fund your future" to "fund today."
How to Calculate Your Coast FIRE Number
The calculation works backward from your full FIRE number. You need to know:
- Your full FIRE number (annual retirement expenses × 25, or divided by your chosen withdrawal rate)
- Your target retirement age
- Your current age
- An assumed annual investment return (typically 7% in real terms, adjusted for inflation)
The formula is:
Coast FIRE Number = Full FIRE Number ÷ (1 + growth rate)^years until retirement
Example:
Full FIRE Number: $1,500,000
Current age: 35
Target retirement age: 60
Years of growth: 25
Assumed real return: 7%
Coast Number = $1,500,000 ÷ (1.07)^25
Coast Number = $1,500,000 ÷ 5.427
Coast Number ≈ $276,424
If you have $276,424 invested today at age 35 and never add another dollar, it will grow to approximately $1,500,000 by age 60 — assuming a 7% real annual return. That's your Coast FIRE number.
Why the Growth Rate Assumption Matters
The 7% figure is commonly used because it approximates the long-term inflation-adjusted historical return of a diversified equity portfolio (based on S&P 500 historical data). But small changes in this assumption produce large changes in your Coast number.
- At 6% real return: Coast Number = $1,500,000 ÷ (1.06)^25 = $350,122
- At 7% real return: Coast Number = $1,500,000 ÷ (1.07)^25 = $276,424
- At 8% real return: Coast Number = $1,500,000 ÷ (1.08)^25 = $219,268
The more conservative your return assumption, the larger the portfolio you need to have already saved. When calculating your Coast number, err on the side of conservative — if real returns exceed your assumption, you'll arrive at retirement with more than you planned.
What Changes When You Hit Coast FIRE
Reaching Coast FIRE doesn't mean you retire — it means the financial pressure changes completely. You no longer need a high-income job. You no longer need to maximize your savings rate. You only need to earn enough to cover your current living expenses.
This opens significant lifestyle possibilities:
- Switching to a lower-stress, lower-paying job you actually enjoy
- Going part-time or freelance
- Taking extended time off without derailing your retirement timeline
- Moving to a lower cost-of-living area and working less
- Starting a business with less financial risk
For many people, the Coast FIRE milestone provides more day-to-day freedom than full FIRE — because it arrives years or decades earlier, while you're still young enough to fully enjoy the flexibility.
Coast FIRE vs. Barista FIRE: What's the Difference?
These two strategies are often confused. The key distinction is this:
- Coast FIRE: Your existing portfolio will compound to your full FIRE number on its own. You earn enough from work to cover expenses and add nothing to investments.
- Barista FIRE: Your existing portfolio plus part-time income together cover your total expenses. You're semi-retired — you're working, but only part-time, and your portfolio plus that income fund your life.
With Coast FIRE, your future is already funded — you're just living for today. With Barista FIRE, your portfolio and your part-time work together fund both today and your eventual full retirement.
The Psychological Shift at Coast FIRE
One thing the calculators don't capture: the mental shift that comes with hitting Coast FIRE can be profound. The constant pressure to accumulate — to max the 401(k), to increase the savings rate, to hit the next milestone — lifts. Many people who reach Coast FIRE report feeling genuine financial freedom for the first time, even though they're still working.
The flip side: some people find it disorienting. If you've organized your financial life around growth and accumulation, the shift to "just cover expenses" can feel like you're doing something wrong, or like you're falling behind. You're not. You're just operating at a different phase of the journey.
If you find yourself there and struggling with that psychological shift, the Burnout vs. FIRE Diagnostic on this site can help clarify what you actually want your working life to look like from here.
Are You Already at Coast FIRE?
Many people who've been investing consistently since their mid-to-late 20s are already at or near their Coast FIRE number by their mid-30s — without realizing it. The calculation takes less than a minute.
→ Use the Free Coast FIRE Calculator
Enter your current portfolio, age, target retirement age, and expected return — and find out whether you've already earned the right to stop rowing.
Want a complete picture of where you stand? Empower's free dashboard aggregates all your investment accounts in one place so you always know your exact portfolio value — essential for tracking your Coast FIRE progress.
Disclaimer: This article is for educational purposes only and does not constitute financial, tax, or investment advice. Consult a qualified financial professional before making retirement planning decisions.