What Is Coast FIRE? The Milestone Before Retirement
By Retire Growth · Updated 2026-10-27 · No independent professional financial review is claimed.
What Coast FIRE does—and does not—mean for your savings, work and current living costs.
Coast FIRE describes a specific savings milestone: investments already held could grow to a later retirement target without more deposits, under the assumptions you choose. It does not mean those investments can pay today's bills. The distinction between the savings milestone and the retirement date is the starting point for using the idea well.
Two budgets, two different jobs
There is a current budget to cover while the investments grow. There is also a future retirement budget that those investments may eventually support. Coast FIRE focuses on the second budget. A paycheck or another source would still need to cover the first.
Taking money from the portfolio during the coast period changes the calculation. So does letting savings sit in an asset whose expected growth differs from the assumed return. The simple model leaves investments untouched and applies a constant real growth factor.
The number depends on the date
Suppose an illustrative retirement target is $1,200,000 in today's purchasing power. With a 4% real annual growth assumption and 30 years remaining, the Coast number is approximately $370,000: the target divided by 1.04 to the power of 30. These are example assumptions, not a forecast or a personal goal.
Moving retirement closer leaves less time for assumed growth. Increasing the spending target also increases the starting balance required. There is no universal Coast number independent of those choices.
What happens after the milestone?
Within the model, new deposits are no longer required to reach the selected future target. In real life, circumstances can change. Expenses may rise, investments may lose value, or retirement may happen earlier than planned. A calculation made once does not resolve those uncertainties permanently.
The Coast FIRE calculator shows both the no-new-deposits path and a continued-savings path. Comparing them helps reveal what is being assumed when someone says they can “coast.” It does not decide that they should stop saving.
A useful next question
Before interpreting the result, identify which budget the spending input represents, whether taxes and health costs are included, and when the portfolio would actually need to provide income. Then test more than one growth assumption.
To locate a possible milestone while you keep contributing, read how Coast FIRE age is calculated. To compare this idea with other ways of approaching financial independence, see Coast versus Full, Lean and Barista FIRE. The methodology gives the exact formulas and rounding rules.
Updated October 27, 2026. Educational content; no independent professional financial review is claimed.