Question 1

What is Coast FIRE?

Accepted Answer

Coast FIRE is the point where you have saved enough that compound interest alone — with zero additional contributions — will grow your portfolio to your target retirement number by your chosen retirement age. Once you hit Coast FIRE, you only need to earn enough to cover your current living expenses. You never need to save another penny for retirement.

Question 2

How is the Coast FIRE number calculated?

Accepted Answer

The Coast FIRE number equals your target retirement balance divided by (1 + expected return) raised to the power of years remaining until retirement. For example, if you need $1.5M by age 65 and expect 7% returns, at age 30 you'd need $1,500,000 / (1.07)^35 = $140,000. Once you have $140,000 invested at 30, compound growth handles the rest.

Question 3

What is the difference between Coast FIRE and regular FIRE?

Accepted Answer

Regular FIRE means you have enough saved RIGHT NOW to cover all living expenses indefinitely using the 4% rule. Coast FIRE means you have enough saved that compound growth will get you to your FIRE number by a future date — you still need to work to cover current expenses, but you never need to save for retirement again. Coast FIRE is typically reached 10-20 years before full FIRE.

Question 4

What return rate should I use for Coast FIRE calculations?

Accepted Answer

Most Coast FIRE calculators use 7% as a default, which represents the historical inflation-adjusted return of the S&P 500. Conservative planners might use 5-6%, while more aggressive estimates use 8-10% nominal (not inflation-adjusted). The key insight: even small changes in expected return dramatically affect your Coast FIRE number, so using a conservative estimate provides a safety margin.

Question 5

What should I do after reaching Coast FIRE?

Accepted Answer

After Coast FIRE, you have incredible flexibility. You can: switch to a lower-paying but more fulfilling job, go part-time, start a business without financial pressure, take a sabbatical, travel, or keep working and accelerate toward full FIRE. The point is that retirement savings are no longer a factor in your career decisions. You're working because you want to, not because you have to save.

Coast FIRE Calculator

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Coast FIRE at Age 38

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Frequently Asked Questions

What is Coast FIRE?

How is the Coast FIRE number calculated?

What is the difference between Coast FIRE and regular FIRE?

What return rate should I use for Coast FIRE calculations?

What should I do after reaching Coast FIRE?

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