Your FIRE number and years to reach it.
FIRE number
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Years to financial independence
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Two questions every FIRE plan has to answer
Financial independence comes down to two numbers. How big a pot do you need before work becomes optional, and how long will it take to get there? This calculator answers both. It sizes your target from your annual spending and a chosen safe withdrawal rate, then runs a month-by-month projection from your current investments, your monthly contributions, and an expected real return until the pot reaches the target. The output is a finishing line and a countdown to it.
The target rests on the safe withdrawal rate, the slice of your portfolio you can draw each year and reasonably expect never to run out. The famous version is the 4 percent rule, which implies a pot of 25 times your annual spending. The calculator defaults to a more cautious 3.5 percent, which is 28.6 times spending, because the original research was American and UK investors face different market history and sequence risk. Lowering the rate raises the target, so the choice has a large effect on the finishing line.
Sixteen years to independence on £32,000 a year
Take a saver who wants £32,000 a year to live on, uses a 3.5 percent withdrawal rate, has £150,000 invested already, adds £2,000 a month, and expects a 5 percent real return after inflation. The target is £32,000 divided by 3.5 percent, which is £914,286. Compounding the existing pot and the monthly contributions at a real 5 percent, the projection reaches that target in 192 months, or 16.0 years.
| Input | Value |
|---|---|
| Annual spending in retirement | £32,000 |
| Safe withdrawal rate | 3.5% (28.6x spending) |
| FIRE number | £914,286 |
| Starting investments | £150,000 |
| Monthly contribution, real return | £2,000 at 5% |
| Years to financial independence | 16.0 years |
The curve shows the pot climbing from £150,000 towards the £914,286 target. Notice the acceleration: the early years are slow because contributions do most of the lifting, while in the later years compounding takes over and the line steepens.
The UK wrappers that change the path
This tool is wrapper-agnostic; it treats your pot as one number. In practice where you hold the money shapes when you can spend it. A stocks and shares ISA, with its £20,000 annual allowance, can be drawn at any age completely free of tax, which makes it the workhorse of early retirement before pension age. A pension is even more tax-efficient on the way in, with relief at your marginal rate and a £60,000 annual allowance, but you cannot touch it until the minimum pension age, currently 55 and rising to 57. Many UK FIRE plans therefore build an ISA bridge to cover the years between stopping work and unlocking the pension, then lean on the pension and eventually the State Pension after that.
Why does the order of investment returns matter so much?
This is sequence risk, and it is the quiet danger that withdrawal rates are designed to guard against. Two retirees with the same average return over thirty years can end up in completely different places if one suffers a market crash in their first few years of drawing down. Selling units to fund spending while prices are depressed locks in losses the portfolio never recovers from. That is why a cautious withdrawal rate and a cash buffer to cover a year or two of spending, so you are not forced to sell into a falling market, matter far more in the early years of retirement than later on.
Why use a real return rather than a nominal one?
Because your spending target is in today's money. By entering a real return, the growth already net of inflation, the projection keeps everything in present-day pounds, so the £914,286 target means the same purchasing power throughout. If you instead used a nominal return like 7 or 8 percent, you would need to inflate the spending target each year to compare like with like, which is easy to get wrong.