Coast FIRE
Save now, coast to retirement
Reach your coast number → let compound growth handle the rest
Coast FIRE is a powerful FIRE strategy where you save aggressively early in your career until your portfolio reaches a specific threshold — after which you only need to earn enough to cover current expenses. Compound interest does the heavy lifting for retirement.
How Coast FIRE Works
The math behind Coast FIRE is simple: if you invest enough money now, compound interest will grow it to your full FIRE number by the time you reach traditional retirement age — even if you never invest another dollar.
Coast FIRE Formula
Coast FIRE Number =
FIRE Number ÷ (1 + r)n
r = annual return rate, n = years until retirement
Example Calculations (7% return, $1M FIRE number):
The Coast FIRE Journey
Phase 1: Aggressive Savings
Save 40-60% of income and invest in low-cost index funds. The goal is to reach your Coast FIRE number as fast as possible.
Phase 2: Reach Coast FIRE Number
Once your portfolio hits the Coast number, you have optionality. You can work for enjoyment rather than necessity.
Phase 3: Coast!
Work only enough to cover current expenses. The portfolio grows on its own. Take sabbaticals, go part-time, change careers.
Phase 4: Full FIRE
At traditional retirement age, your portfolio has grown to your full FIRE number through compound growth alone.
Pros & Cons
Advantages
- Removes retirement saving pressure once threshold is reached
- Allows career pivots to meaningful/lower-paying work
- Compound growth does the heavy lifting
- Achievable intermediate goal that feels real
- Reduces financial stress significantly
Disadvantages
- Still working until traditional retirement age
- Requires discipline not to touch investments
- Inflation over long periods is a risk
- Healthcare still needs to be funded
- Must trust long market growth assumptions
Frequently Asked Questions
What is Coast FIRE?
Coast FIRE means saving enough early in life that — even without additional contributions — your investment portfolio will grow to your full FIRE number by traditional retirement age through compound growth alone.
How do I calculate my Coast FIRE number?
Coast FIRE Number = FIRE Number ÷ (1 + return rate)^years to retirement. For example: $1M FIRE Number, 30 years to retirement at 7%: $1,000,000 ÷ (1.07)^30 = ~$131,000 Coast FIRE Number.
What do you do after reaching Coast FIRE?
After reaching Coast FIRE, you only need to earn enough to cover your current living expenses. You can take lower-paying but more meaningful work, go part-time, take sabbaticals, or work in lower-stress roles — all without worrying about retirement savings.
What is the difference between Coast FIRE and Barista FIRE?
Coast FIRE focuses on the math — having enough invested that growth alone will fund retirement. Barista FIRE is similar but emphasizes the lifestyle aspect: working enjoyable part-time jobs (like a barista) that also provide benefits like health insurance.
Calculate Your Coast FIRE Number
Our calculator shows your Coast FIRE number alongside your full FIRE projection.
Open FIRE Calculator