What is Coast FIRE?
Coast FIRE is a milestone on the path to financial independence. You reach it the moment you've invested enough that compound growth alone — with no further contributions — will grow your portfolio to your full FIRE number by the time you hit traditional retirement age.
Once you're "coasting," you no longer have to save a single additional dollar for retirement. You only need to earn enough to cover your current living expenses. That's a profound shift: the pressure to max out every account disappears, and you're free to take a lower-paying but more fulfilling job, cut back your hours, or simply stop stressing about retirement savings.
How the Coast FIRE calculator works
The calculator first works out your full FIRE number — the portfolio you'll need at retirement — then discounts it backward to today using your expected return:
It then projects your current invested assets forward with zero new contributions. If that curve reaches or exceeds your full FIRE number by your target retirement age, you've hit Coast FIRE. The chart shows exactly that: your assets compounding on their own against the FIRE target line.
The inputs
- Current age & target retirement age — the gap is how many years compounding has to work.
- Current invested assets — what you have working in the market today.
- Annual retirement expenses — drives your full FIRE number.
- Real return rate — inflation-adjusted growth, often assumed near 7% for stocks.
- Safe withdrawal rate — commonly 4%, which sets your FIRE number at 25× expenses.
A Coast FIRE example
Say you're 30, want to retire at 65, and expect to spend $45,000 a year. At a 4% withdrawal rate your full FIRE number is $1,125,000. With 35 years of 7% real growth ahead, you'd only need about $105,000 invested today for compounding to carry you the rest of the way. Hit that number and you're Coast FIRE — everything after that is a bonus that lets you retire even earlier.
The younger you are, the smaller your Coast FIRE number, because time does more of the heavy lifting. This is why investing aggressively in your 20s is so powerful — a relatively modest sum can put you on autopilot for decades.
Coast FIRE vs Barista FIRE vs full FIRE
Coast FIRE
Stop investing, keep working to cover expenses. Compounding handles the rest until retirement.
Barista FIRE
Part-time work covers some expenses; your portfolio covers the rest. Scale back work sooner.
Barista FIRE calculator →The order
Most people hit Coast FIRE first, then Barista FIRE, then full FIRE as the portfolio keeps compounding.
Frequently asked questions
What is Coast FIRE?
Coast FIRE is the point where you have invested enough that, with no further contributions, compound growth alone will carry your portfolio to your full FIRE number by traditional retirement age. You only need to earn enough to cover current expenses.
How is the Coast FIRE number calculated?
Coast FIRE number = your full FIRE number divided by (1 + real return rate) raised to the number of years until retirement. It is the amount you need invested today so growth alone reaches your FIRE number by retirement age.
What is the difference between Coast FIRE and Barista FIRE?
With Coast FIRE you stop investing but still work to cover living expenses until retirement. With Barista FIRE, part-time work covers only part of your expenses while your portfolio covers the rest, letting you scale back work sooner.
Do I ever have to invest again after reaching Coast FIRE?
No. Once you hit your Coast FIRE number, compounding is projected to reach your full FIRE target on its own. You only need income to cover current expenses, though continuing to invest would let you retire even earlier.