Find how long it takes to reach a target (for example £1 million), from a starting amount, a monthly contribution and an annual return.
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Enter the target, the starting amount, the monthly contribution and the annual return. See how long it takes to reach the target.
The calculation assumes a constant annual return and monthly contributions. The real market fluctuates, and inflation reduces the purchasing power of the target.
Time needed 19 years 2 monthsStandard financial formulas (time value of money). Instant in-browser calculation, no account, no data sent. Returns are not guaranteed — markets fluctuate. Last updated: 11 July 2026 · Bank of England base rate.
⚖︎ Results are for informational purposes and do not constitute tax advice. For specific situations, consult a licensed accountant or the relevant tax authority.
The portfolio’s growth is simulated month by month, with compound return and monthly contribution, until the target is reached:
With £10,000 to start, £2,000/month and 7% return, you reach £1,000,000 in about 19 years.
It depends on the starting amount, the monthly contribution and the annual return. For example, with £10,000 to start, £2,000/month and 7% return, you reach £1,000,000 in about 19 years.
The portfolio’s monthly growth is simulated: the balance is multiplied by the monthly return and the contribution is added, until it reaches the target. The number of months divided by 12 gives the years.
The higher the monthly contribution and the return, the less time it takes. A larger contribution shortens the time dramatically, as does a better compound return.
A prudent benchmark is 7%, close to the historical long-term return of major stock markets. Higher returns speed things up but come with more risk and volatility.
Yes. A larger starting amount benefits from compounding for more time and shortens the period. Over the long term, though, the steady contribution and the return matter most.
Early on, the monthly contribution has the biggest impact because the portfolio is small. As it grows, the compound return becomes the main engine of growth.
In the UK, a Stocks & Shares ISA lets you invest up to £20,000 a year with tax-free growth, and pensions add tax relief. Using these wrappers keeps more of the compounding for you.
Yes. £1 million in 20 years will have less purchasing power than today. For a realistic goal, adjust the target for expected inflation.