Coast FIRE vs Lean FIRE: Which Strategy Fits Your Life?
Reference FIRE Number
$750K
Target Age
65
Monthly Needed
$500
Coast FIRE and Lean FIRE both target early financial freedom on modest means, but they work very differently. Lean FIRE means accumulating a full FIRE number — typically $625K–$1M — and retiring completely from paid work on $25,000–$40,000/year in spending. Coast FIRE means reaching a smaller threshold now ($75K–$200K typically), then working just enough to cover current expenses until traditional retirement. Both are attainable on middle incomes, but the timelines and lifestyle implications differ substantially.
The Coast FIRE number (the amount you need invested today) is much smaller than the Lean FIRE number — but Coast FIRE requires continued earned income. At age 30 with 35 years to retirement, the coast number for a $750K Lean FIRE target is just $75K (7% returns, 35 years). That's far faster to accumulate than $750K itself. But reaching $75K and "coasting" still means working for 35 years to cover expenses — just without the pressure of retirement saving.
Lean FIRE achievers can stop working entirely once they hit the number. A 30-year-old who reaches $750K can potentially retire completely — living on $30,000/year from a 4% withdrawal. Coast FIRE at the same age requires the same $75K to be invested, but then you must continue earning $30,000+/year for the next 35 years. For people who hate their work, Lean FIRE's complete freedom is worth the additional accumulation time. For those who like their work but hate the financial pressure, Coast FIRE delivers relief much faster.
The practical choice often comes down to timeline and work tolerance. If you can live on $30K/year and want to stop working at 40, Lean FIRE is your path — save aggressively for 10–15 years. If you earn $70K and enjoy your work but want to reduce pressure, switch careers, or go part-time — and you're willing to work until 65 in some capacity — Coast FIRE delivers relief in 5–8 years rather than 15. Many FIRE practitioners move from Coast FIRE to Lean FIRE as their portfolio grows during the coast phase.