Millionaire Timeline Calculator
Calculate how long until you become a millionaire.
What this calculator does
This calculator solves for time rather than for a final balance. Given what you hold now, what you add each month, and the return you expect, it works out how many years until your investments cross £1 million and the age at which that happens, alongside a year-by-year table.
That table separates contributions from growth, and the crossover point where cumulative growth first overtakes cumulative contributions is the figure worth finding. Before it, you are carrying the portfolio. After it, the portfolio carries itself, and the remaining distance closes much faster than the distance already travelled.
When to use it
It is best used comparatively rather than as a plan. Testing an extra £200 a month against your current contribution turns a vague intention into a specific number of years, which motivates far better than an abstract percentage of salary.
It also prices decisions usefully. A £400 monthly car finance agreement has a cost expressible in months added to your timeline. And running the same figures at 5 percent and 7 percent shows how much of the answer rests on an assumption you do not control, which is worth knowing before you rely on it.
Understanding the inputs
Current savings should include stocks and shares ISAs, general investment accounts and pensions if you count pension money toward the goal, but not cash held for emergencies and not property. Monthly contribution should include employer pension contributions and tax relief where relevant, since all of it compounds identically.
Expected return should be net of charges. Take a long-run equity figure of 7 to 8 percent and subtract your platform fee and ongoing fund charges to get a realistic input, which for most people lands between 5 and 6.5 percent. Because the output is a number of years, small changes here move the answer substantially.
How is this calculated?
Solve for n in the FV formula: Target = PV(1+r)^n + PMT×[(1+r)^n − 1]/r.
A worked example
A 30-year-old with £15,000 invested, adding £700 a month at 6 percent, reaches £1 million in roughly 33.4 years, at about age 63. Contributions over that period total around £280,000, so more than 70 percent of the final balance comes from growth rather than deposits.
Raise the contribution to £1,000 a month and the timeline shortens to about 29 years, arriving at 59. Alternatively keep £700 a month but achieve 8 percent instead of 6, and it falls to about 28 years. Both routes save roughly five years, but only one of them is under your control.
Limitations and assumptions
This is a projection under fixed assumptions rather than a prediction. It applies a constant monthly return, which no fund delivers. Because it solves for the moment a threshold is crossed, volatility matters more than in a balance projection: a portfolio can pass a million and fall back below it, and the crossing year depends heavily on the order returns arrive in.
It also holds contributions flat throughout, ignores charges unless you deduct them from the return, ignores tax on the way out, and takes no account of inflation eroding what a million actually buys. Treat the output as a broad range of years and revisit it whenever your contribution changes.
Common Questions
- How long does it take to save £1 million?
- With £15,000 invested and £700 a month at 6 percent, roughly 33 years. Increase that to £1,000 a month and it drops to about 29. Contributions dominate the early years, so raising the monthly amount shortens the timeline far more reliably than hoping for a better return.
- Can I do this entirely inside an ISA?
- Only partly. The ISA allowance is £20,000 per tax year, about £1,666 a month across all ISA types, so contributions above that need a pension or a general investment account. Reaching a million in ISAs is achievable over a long career, and the whole balance is then free of income and capital gains tax.
- Does a pension get there faster?
- Usually, because of tax relief and employer contributions. A £100 pension contribution costs a basic rate taxpayer £80 and a higher rate taxpayer £60 of take-home pay, and salary sacrifice saves National Insurance on top. The trade-off is that the money is locked until 55, rising to 57 from April 2028.
- Why does progress feel so slow early on?
- Because nearly all of a small balance is money you deposited. Six percent on £40,000 is £2,400 a year, which is barely noticeable. Six percent on £700,000 is £42,000 a year, comfortably more than most people contribute. The curve steepens continuously, so the last stretch is far quicker than the first.
- Will £1 million be worth much by then?
- Considerably less than today. At 2.5 percent inflation, £1 million in 33 years has the purchasing power of roughly £438,000 now. Treat it as a milestone rather than a target. What matters is what it funds: at a 4 percent withdrawal rate a million supports about £40,000 a year gross.
- What return should I assume?
- Global equity funds have returned around 7 to 8 percent nominally over long periods, but you need to deduct platform and fund charges. Five to six percent net is a defensible planning figure. Since this calculator solves for time rather than balance, an optimistic return does not inflate a number, it silently removes years.
- Do charges really matter that much?
- Yes. A total cost of 1.2 percent against 0.25 percent is nearly a full percentage point of return, which on a three-decade timeline is worth several years. Check your platform fee and the ongoing charges figure of each fund; the combination is what actually reduces your return.
- Should my contribution rise over time?
- It should, and this calculator assumes it does not, which makes the projection conservative. Directing each pay rise into contributions before it reaches your current account is the most effective habit most savers can adopt. Try rerunning with the contribution you expect to be making in five years.
- What about tax on the way out?
- It depends entirely on the wrapper. An ISA million is spendable in full. A pension million gives 25 percent tax-free, capped by the lump sum allowance of £268,275, with the rest taxed as income. In a general investment account, dividends and capital gains are taxed as you go and the annual exemptions are now small.
Related calculators
- FIRE (Financial Independence, Retire Early) CalculatorCalculate your (Financial Independence, Retire Early) number and how long until financial independence.
- Net Worth Projection CalculatorProject your net worth growth over time based on assets, savings, and debt payoff.
- Compound Interest CalculatorCalculate compound interest growth over time with optional deposits.