Coast FIRE is the most relaxed member of the FIRE family. The idea: save aggressively for a stretch early in your career, then stop adding to retirement accounts entirely and let compounding carry that balance to a full nest egg by traditional retirement age. From then on, your job only has to cover today’s bills — the retirement part is already handled.
It trades the sprint of early retirement for something gentler: front-load the hard saving, then buy yourself decades of breathing room.
How coasting works
The engine is compound growth over a long runway. Money invested in your twenties or thirties has thirty-plus years to grow before you touch it, so a relatively modest sum today can balloon into a full retirement fund without a single additional contribution. Once you have invested that critical amount, you have hit “Coast FIRE,” and fresh savings become optional.
Coast FIRE separates two jobs your paycheck usually does at once — funding retirement and funding today. Finish the first early, and your income is freed to do only the second.
The coast number
Your coast number is the amount you need invested now so that, with no further contributions, it grows into your full retirement target by your chosen date. It depends on three inputs: your eventual target (often the 25x-spending figure), the years of growth remaining, and an assumed rate of return.
- More years to grow means a smaller coast number today — time does the heavy lifting.
- A younger start is a genuine superpower here, because compounding rewards the longest runway.
- The return assumption matters. A more optimistic rate shrinks the number on paper but leans harder on markets cooperating.
Because the whole plan rides on that assumed return, it is wise to be conservative and to check in periodically. A long stretch of weak returns can mean you have to top up contributions after all — coasting is a plan, not a promise.
Why people choose it
Coast FIRE appeals to anyone who wants flexibility without extreme frugality forever. Once you are coasting, you can switch to lower-paying but more meaningful work, take career breaks, or simply spend more of what you earn — knowing the retirement account is quietly compounding in the background. It is a middle path between saving nothing and grinding toward early retirement.
Same idea, US or Canada
The mechanics do not care about your flag. Fund tax-advantaged accounts early — 401(k)s and IRAs in the U.S., RRSPs and TFSAs in Canada — then let them ride. The tax-free growth in a Roth or TFSA is especially powerful over a multi-decade coast, since none of that compounding is taxed on the way out. Wherever you are, the recipe is the same: save hard early, then let time and growth finish the job.