What is Coast FIRE?
Coast FIRE is the point where you've saved enough that compound growth alone will carry you to a traditional retirement — even if you never save another dollar.
Most FIRE conversations focus on the finish line: you stop working entirely. Coast FIRE asks a narrower, more practical question: how long until you can stop pushing?
The two phases
Phase 1 — The Push: You save aggressively, invest consistently, build your portfolio as fast as possible. Savings rate is high. Lifestyle may be constrained.
Phase 2 — The Coast: You ease off. Reduce savings to zero or near-zero. Let compound growth do the rest. You might switch to a lower-paying job you enjoy more. Or just breathe.
The math
Your Coast FIRE number is the amount you need invested today to reach your full FIRE number by age 65 — with no additional savings, using average market returns.
r = expected annual return | n = years until traditional retirement
Once you hit that number, you're done saving. The market takes over. Every year after that is optional.
The four FIRE strategies
- Coast FIRE — Stop saving. Let compound growth finish the job. Work becomes optional but still available.
- Fat FIRE — Retire early with a large portfolio. More than you need. 4% withdrawal barely scratches the principal.
- Lean FIRE — Retire early on a minimal budget. Barista FIRE is a variant: part-time income covers expenses, portfolio handles the rest.
- Barista FIRE — Part-time work covers your expenses. Portfolio withdrawals handle the rest. Lower savings required, but you still work.
Who Coast FIRE is for
- Early career with decades until traditional retirement
- Want to switch to a lower-paying career but can't afford to stop entirely
- Want optionality — work because you want to, not because you have to
- Tired of optimizing every dollar and want a clear signal that you're far enough
Try the calculator
Enter your current age, target retirement age, annual expenses, and expected return. Get your exact Coast FIRE number in under a minute.
The key insight
Compound interest is the most powerful force in personal finance — but only if you give it time. Coast FIRE is a strategy to not interrupt it. Once your money is working, the goal is to not get in its way. Every dollar saved in your 20s or 30s that sits in the market for 30 years is worth 3–4x a dollar saved in your 40s. Coast FIRE quantifies exactly how long you need to push before you can step back and let math take over.
Coast FIRE vs Full FIRE, Side by Side
The two strategies share the same destination and differ in the route. Full FIRE retires you today: your portfolio must pay your entire living expense right now, which means a much larger number and a higher stress of sequence-of-returns risk from the day you stop working. Coast FIRE retires you later: your portfolio only needs to be large enough that compound growth finishes the job by traditional retirement age, and your income keeps coming in the meantime.
| Dimension | Full FIRE | Coast FIRE |
|---|---|---|
| Retirement happens | Now | Traditional retirement age |
| Portfolio must fund | 100% of spending, immediately | 0% of spending; growth does the rest |
| Typical target (2026 dollars) | $1.5M–$2.5M+ | $300k–$700k |
| Risk profile | Sequence-of-returns risk from day one | Time in market absorbs volatility |
| What it frees you from | Work entirely | The savings obligation, not the job |
The trade-off is explicit: Full FIRE buys immediate freedom at a much higher number and higher near-term risk; Coast FIRE buys a smaller, earlier number and keeps your career as a safety net. For most people in their 20s and 30s, Coast FIRE is the rational starting point — you can always accelerate to Full FIRE later, but you can't un-live the years you spent saving too slowly.
Common Misconceptions
"Coast FIRE means I can stop working." No. It means you can stop saving aggressively. You keep working, keep earning, and your portfolio compounds in the background. The job is your income; the portfolio is your insurance policy against future you needing it.
"Coast FIRE is a lazy strategy." The opposite. It requires you to save a large fraction of your income for a decade or more, then have the discipline to not pull it out. The hard part isn't the saving — it's the restraint that comes after.
"Once I hit the number, I can rebalance into bonds." Usually not. You still have 20-25 years of compounding ahead of you. Shifting to a low-volatility allocation at 40 when you need the growth to finish the job is the same mistake as someone who shifts to cash after a market drop — you're selling your way out of the very engine that's carrying you to the destination.
"Coast FIRE works for everyone." It works best for people with 15+ years to retirement age, a stable income, and a spending level they can sustain without the portfolio. If your spending is higher than your income minus savings, or your job is genuinely unstable, Coast FIRE is a bridge, not a plan.
Assumes historical average market returns (~7% after inflation) and a 4% safe withdrawal rate. Your actual results will vary. Educational use only.