Coast FIRE: when you're done saving but not done working
Coast FIRE is the moment when your portfolio is large enough to grow into your full FIRE number on its own, without any further contributions. You can stop saving for retirement and let compounding finish the job. The work you do from that point forward only has to cover your current expenses, which changes everything: the job you take, the risks you tolerate, and the way you spend your time. Coast FIRE arrives years before traditional FIRE for most people who start early.
The concept, in plain language
Compound growth is the engine. Time is the multiplier. If you save aggressively in your twenties and early thirties, you can build a portfolio that, left completely alone, will grow into a full retirement number by the time you actually want to retire. The math is just present-value-of-future-money. A dollar invested at age 30 turning into roughly seven dollars by age 65, assuming 5% real returns. The earlier the dollar lands, the harder it works.
Coast FIRE is the milestone where you've banked enough of those early dollars. The portfolio is now large enough that compounding alone gets you to your retirement number. You can stop contributing to retirement entirely. The work you continue to do only needs to cover today's bills, not tomorrow's nest egg.
This is fundamentally different from FIRE itself. FIRE means you can stop working entirely. Coast FIRE means you can stop saving for retirement, but you still need to work to cover your current expenses. The career-pivot leverage of Coast FIRE is enormous. You're free to take the job that pays less but means more, the role with worse benefits but better hours, the start-up gig that might fail, the move to a city that costs more. You no longer need the job to fund a future. The portfolio is funding the future on its own.
Run the numbers on your own situation
The calculator below tells you whether you've already hit Coast FIRE, and if not, how far away you are. Three inputs: what your portfolio is worth today, what you spend per year, and how many years you have until your target retirement age. Plug them in.
Coast FIRE calculator
Are you already at Coast FIRE? Move the sliders to see how your current portfolio compares to the amount you'd need today for compounding alone to grow it into your full FIRE number by retirement.
What the result actually means
If your current portfolio is at or above the Coast FIRE number, congratulations. The math says you can stop contributing to retirement starting today, and your portfolio will grow into your full FIRE number on its own. That doesn't mean you should stop working. It means you don't have to work specifically to fund retirement. The savings rate that's been driving your career decisions can come down to whatever you actually need to cover current expenses.
If you're not there yet, the gap tells you how much more you need to invest before you can ease off the gas. Two ways to close that gap faster: invest more this year (the obvious one), or extend your retirement horizon by a few years (the less obvious one, but mathematically powerful because of how compounding works). A 35-year-old saving toward age 65 has a much smaller Coast FIRE number than a 35-year-old targeting age 50.
Coast FIRE milestones at different ages
Here's a reference table to anchor the concept. Same assumptions as the calculator's defaults: $60K annual cost of life, 4% safe withdrawal rate (so a $1.5M FIRE target), 5% real annual return, target retirement age of 65.
If your invested portfolio is at or above the number for your age, you're already coasted. From this point forward, every dollar you save is a dollar that pulls your retirement date earlier or pushes your retirement spending higher. It's no longer required, just useful.
What you actually do once you've coasted
Most people who hit Coast FIRE early don't actually stop saving. The habits that built the portfolio in the first place are the same habits driving the savings rate, and habits are hard to turn off. What changes is the orientation. You stop saving because you have to. You start saving because you want to.
Three reasonable moves once you've coasted:
Keep saving and pull retirement earlier. If your Coast FIRE number assumed retirement at 65 and you keep saving aggressively, you can hit your full FIRE number well before 65. Coast FIRE at 35 with continued contributions might mean true FIRE at 50 or 55 instead. The math compounds in your favor.
Keep saving and increase your future spending. Same dynamic but applied to lifestyle instead of timeline. If you stay on your current savings rate, your eventual portfolio will be larger than $1.5M, which means a higher annual spend in retirement. You traded the same effort for a more abundant retirement instead of an earlier one.
Take the savings rate down to zero and use the income for now. The original Coast FIRE thesis. Stop contributing to retirement, take the money that was going into the 401(k) and use it for things that matter to you today. Travel. A house. A kid's education. A career pivot that pays less but feels right. The portfolio is no longer pulling on the present.
None of these is wrong. The right answer depends on what you want, which is the kind of question that becomes interesting only after the financial pressure eases. Coast FIRE is the moment that pressure starts to ease.
The calculator above uses real returns (inflation-adjusted), which means the FIRE target stays in today's dollars and the math works regardless of when you read this. If you use nominal returns (typically 7-8% for a stock-heavy portfolio), the numbers look better but the FIRE target needs to inflate too. Real returns keep the math honest. 5% is a reasonable long-run real return assumption for a diversified equity portfolio. Use 4% if you want to be conservative; 6% if you want to be optimistic.
Coast FIRE vs Barista FIRE vs full FIRE
The three concepts get conflated a lot. They're meaningfully different.
Full FIRE: portfolio covers your entire annual cost of life forever. You don't have to work for income, period. The classic 25x expenses target.
Barista FIRE: portfolio is large enough to cover most of your expenses, with part-time work covering the rest. You still work, but the work is optional in any given year and the income is meaningful.
Coast FIRE: portfolio will grow into your full FIRE number on its own. You still work full-time to cover current expenses, but you've stopped saving for retirement. The future is funded; only the present requires effort.
Coast FIRE arrives first chronologically for almost everyone. Most aggressive savers hit Coast FIRE in their early-to-mid thirties, Barista FIRE in their early forties, and full FIRE in their late forties or early fifties. The progression isn't required (you can skip Barista FIRE entirely, or never stop accumulating past Coast FIRE), but it's the natural sequence for someone running the standard FIRE playbook.
The mindset shift that comes with Coast FIRE
The financial value of Coast FIRE is straightforward. The psychological value is harder to articulate but bigger.
Once you've coasted, every job you take from that point on is a choice rather than an obligation. You're no longer optimizing for total compensation, you're optimizing for whatever combination of money, meaning, location, and people actually matters to you. The job that pays $30K less but lets you live somewhere you love? Now possible. The career pivot to something you've always wanted to try but couldn't afford to risk? Now possible. The decision to take a sabbatical, or to refuse the promotion, or to leave the company that's been grinding you down? All easier.
The portfolio doesn't make you rich. It makes you free to negotiate with your own life. That's a fundamentally different experience of work, and it shows up years before you're ready to actually retire.
Run the math on your own portfolio this week
If you have any meaningful savings from the last decade, you might be closer to Coast FIRE than you realize. The calculator above takes thirty seconds and tells you exactly where you stand. Knowing the number changes how you think about the next career decision in front of you, even if you choose to keep saving anyway.
The bottom line
Coast FIRE is the underrated milestone in the FIRE journey. It arrives first, it costs the least to reach, and it changes your relationship to work in a way that nothing else does until full retirement. You don't have to chase Coast FIRE on purpose, but if you're saving aggressively in your twenties and early thirties, you'll probably hit it without realizing. The point of the calculator above is to make sure you do realize. Knowing you're coasted, even if you choose to keep saving, is one of the most freeing pieces of math you'll ever run on yourself.