Simple definition
Coast FIRE means you already have enough invested that, without adding another dollar, it should grow to fund your retirement by your target age. So you only need to earn enough to cover current expenses. Think of it like a boulder already rolling downhill: you gave the push, and now momentum carries it.
Why it matters
Coast FIRE can bring real breathing room well before full retirement. Once you reach it, you can ease off aggressive saving, work less, or switch to a job you enjoy, since your nest egg is projected to grow on its own. The growth is an estimate, though, not a guarantee.
Real-life example
Suppose you invest steadily in your twenties and build a balance that, left untouched, is projected to grow into a full retirement fund by your sixties. You have hit Coast FIRE. From here you only need to cover living costs. Because it rests on assumed growth, treat it as an estimate.
Common mistakes
- Treating the projected growth as a guarantee rather than an estimate.
- Reaching Coast FIRE and then spending so much that you dip into the invested money.
- Using an overly optimistic growth rate that overstates how close you are.
- Forgetting that health care and emergencies still need their own planning.
Pro tips
- Use a conservative growth estimate so you do not overstate your progress.
- Once you coast, avoid touching the invested balance and let it compound.
- Keep covering current expenses so you never have to withdraw early.
- Recheck your numbers periodically, since markets and costs can shift.
Related Money Dictionary terms
- FIRE (Financial Independence, Retire Early)A movement focused on saving and investing aggressively so you can stop working decades earlier than the traditional retirement age.
- Financial IndependenceThe point where your savings and investments generate enough income to cover your living costs without needing a paycheck.
- Compound InterestInterest that earns interest — the engine behind long-term growth.
- Savings RateThe share of your income you set aside rather than spend, usually shown as a percentage of your take-home pay.
- Net WorthWhat you own minus what you owe — the clearest scorecard of your financial progress.
Frequently asked questions
How is Coast FIRE different from regular FIRE?
Full FIRE means you have enough to stop working entirely and live off your investments. Coast FIRE is an earlier milestone: you have enough invested to eventually fund retirement without adding more, but you still work to cover today's expenses. It offers flexibility sooner, without needing to quit work completely.
Is the growth in Coast FIRE guaranteed?
No. Coast FIRE rests on an assumption that your invested money will grow at a certain average rate over many years. Markets rise and fall unevenly, so the real outcome may differ. Treat any Coast FIRE number as an estimate, use conservative assumptions, and recheck it over time rather than trusting it blindly.
What can I do once I reach Coast FIRE?
You gain flexibility. Because your invested savings are projected to grow into a retirement fund on their own, you only need income to cover current expenses. Many people use this freedom to work less, switch to a lower-paying job they enjoy, or take more risks, while leaving the nest egg to compound.
Knowing what Coast FIRE means is knowledge — the first half. A brick gets placed when you act on it: estimate whether your current investments, left to grow, could fund retirement by your target age.
Sources & references
More in Wealth Building & Financial Planning
Plain-English education — not personalized legal, tax, or investment advice.