Coast FIRE: the Point Where You Can Stop Saving
There is a balance at which you can stop saving for retirement entirely and still get there. To reach $1.5 million by 60, you need $413,327 at age 30 - and then nothing more, ever. Wait until 40 and the number is $635,174. The gap between those two figures is what starting early actually buys you.
A different question about retirement
Most retirement planning asks: how much do I need to save each month?
Coast FIRE asks something else. How much do I need already, so that I never have to save again?
Not “so I can retire now”. you still need to cover your living costs. But retirement itself would be handled. The money already in the account would grow into your target on its own.
That turns out to be a genuinely useful number, and it is much smaller than people expect.
The numbers
Target: $1.5 million by age 60. Returns of 7% with prices rising 2.5%, which gives a real rate of 4.39%. Using the real rate keeps the target in today’s money - an important detail most calculators skip.
From the Coast FIRE calculator:
| Your age | Years to grow | You need already |
|---|---|---|
| 30 | 30 | $413,327 |
| 35 | 25 | $512,382 |
| 40 | 20 | $635,174 |
| 45 | 15 | $787,395 |
| 50 | 10 | $976,095 |
$413,327 at thirty becomes $1.5 million by sixty with nothing added. Every penny of the remaining $1.09 million is growth.
What this table actually shows
Read it downwards and it makes the case for starting early better than any lecture.
The person who reaches $413,327 by thirty can stop. The person who has not got there by fifty needs $976,095 - more than twice as much - to be in the same position.
That is not because they saved less. It is because they have twenty fewer years of compounding, and those twenty years were doing most of the work.
Where the target comes from
$1.5 million is not arbitrary. It is 25 times $60,000 of annual spending - the inverse of the 4% rule.
That rule is a planning benchmark drawn from studies of how past markets behaved, not a promise about future ones. Treat it as a reasonable starting point rather than a law.
It also assumes nothing else is coming. Any pension or Social Security reduces the pot you need. Every $10,000 of reliable annual income from elsewhere replaces roughly $250,000 of savings - see the Social Security guide for what that income might look like.
The detail that matters most
Notice the calculation uses a real return of 4.39%, not the headline 7%.
This matters enormously. $1.5 million in thirty years will not buy what $1.5 million buys today - at 2.5% inflation, prices roughly double over that period.
Using the nominal 7% would give a coast number around $197,000 instead of $413,327. That would be less than half the truth, and someone acting on it would arrive at sixty with roughly half the buying power they planned for.
If you use another Coast FIRE calculator, check which rate it uses. It is the difference between a useful number and a comforting one.
What reaching it actually means
Almost nobody who hits Coast FIRE stops saving. That is fine, because the value is not in stopping.
What it means is options:
- Take the job you would prefer that pays less
- Drop to four days a week
- Start something risky, knowing retirement is handled
- Carry on saving and retire considerably earlier
The milestone converts anxiety into choice. That is worth more than the number itself.
An honest caution
This assumes a return that arrives smoothly. Real markets do not - some years fall 20%, some rise 30%, and the order matters.
Someone who reaches their coast number and stops saving just before a long flat decade will not be where the arithmetic promised. That is not an argument against the concept, but it is an argument for not treating the number as a finishing line the moment you touch it.
The sensible version: reach it, keep saving something, and enjoy knowing you no longer have to.
What to do
- Work out your target - 25 times your annual spending is a reasonable start.
- Subtract anything else you expect, like a pension.
- Find your coast number for your age and intended retirement date.
- Use a real return, not a nominal one.
- Treat it as options, not an instruction.
Work out your own in the Coast FIRE calculator - it uses a real return so the target stays in today’s money, and shows the age at which your current saving gets you there.
Common questions about coast fire
What is Coast FIRE?
The point where your existing retirement savings will grow into your target on their own, without another penny added. You still have to work and cover your living costs - you just no longer need to save for retirement. It is a milestone, not retirement itself.
How much do I need to coast?
It depends entirely on how long the money has to grow. To reach $1.5 million by 60, you need $413,327 at 30, $635,174 at 40, or $976,095 at 50. The earlier the date, the smaller the number - that is compounding doing the work.
Why use a real return rather than a nominal one?
Because $1.5 million in thirty years will not buy what $1.5 million buys today. Taking 2.5% inflation off a 7% return leaves a real rate of 4.39%, which keeps the target in today's money. Using the nominal 7% would make the coast number look far smaller than it is.
What target should I use?
A common starting point is 25 times your annual spending, which is the inverse of the 4% rule. Spending $60,000 a year gives a $1.5 million target. It is a benchmark, not a guarantee, and it assumes nothing else - no pension, no Social Security - is coming.
Should I actually stop saving once I get there?
Most people do not, and that is sensible. Reaching it means you have options rather than an instruction. You could work less, take a job you prefer that pays less, or carry on saving and retire earlier. The value is in the choice, not the stopping.