Stocks & Shares ISA calculator
See how much your money could grow, based on a representative example and a few assumptions.
Estimated returns of our funds
If you had made a one off payment of £10,000 with monthly payments of £250, after a period of 10 years you will have made contributions worth a total of £40,000.
Take a look at the table below to see what those contributions would return for each of our growth approaches in different market scenarios (how stocks markets might generally perform), compared with cash:
| Market Scenario | Low | Medium | High |
|---|---|---|---|
| Cautious Growth Approach | £36,800 | £50,400 | £68,600 |
| Balanced Growth Approach | £34,600 | £54,100 | £83,100 |
| Adventurous Growth Approach | £30,900 | £56,800 | £101,000 |
| Comparable Cash Return | £45,100 | £45,100 | £45,100 |
Projection generated November 2025
More about our assumptions
What you’ll pay in
We assume you’ll keep making the same regular payments throughout the time you’re investing with us.
ISA allowance and tax
We assume the annual ISA allowance will stay the same. So, we cap your annual payments at that level even if you tell us you want to pay more. We also assume there’ll be no tax implications for taking your money out.
Imagining the future
We consider past performance when estimating possible outcomes for your investment based on how much you invest, for how long and how the market might perform. However, past performance isn’t a reliable guide to future performance – investments can go up or down.
To work out this estimate we do lots of calculations behind the scenes. To keep it reasonable, we ignore both the highest and lowest 5% of results when we show you the estimated value range and the low and high selected market scenario.
Cash returns
To estimate the equivalent potential cash returns we based our forecast returns from a cash (or near cash) investment fund. This simulates the effects of holding cash as an asset, instead of holding cash with a bank.
Considering inflation
We show what your investment might be worth in today’s money, after allowing for inflation. We consider lots of possibilities for inflation, rather than a single fixed % because the rate of inflation can rise and fall over time. Inflation reduces the value of what you can buy in the future as well as the value of your savings.Deducting our charges
We remove our two charges (Account Charge and Annual Management Charge) from the returns as we calculate your estimate, assuming they’ll stay the same throughout the time you’re investing with us.
Rounding things off
Finally, we round our estimates down a bit, just to make the numbers a bit easier to read – remember they’re only a guide and the estimated returns aren’t guaranteed. But we hope they help.
So that’s how we work out your estimate.
Remember, these are only indications. What you get back will depend on how the funds perform, if you make changes to the length of time you’re investing, and if you change the amount you put in.
Remember, our estimates about your future returns aren’t guaranteed. These forecasts are not a reliable indicator of future performance but we hope they help. The value of investments can go up and down, so you may get back less money than you put in. Tax depends on your individual circumstances and the regulations may change in the future.
Octopus Money Direct Growth Approaches
Learn about our investment mix
Higher potential returns and risk
Lower potential returns and risk
The investment mix shows you how much of your money typically goes into the higher risk investments with higher potential returns, and how much goes into the lower risk investments with lower potential returns.
For more info, check out our guide investing money and the risks.
Cautious Growth Approach
Investment Mix
Who is it for?
For people looking to take a slower, cautious approach to growing their money in the long term – and looking to reduce ups and downs along the way.
How we invest your money
Generally, with the Cautious growth approach, more of your money goes into lower risk investments with lower potential returns, and less goes into higher risks with higher potential returns.
Balanced Growth Approach
Investment Mix
Who is it for?
For people who prefer to take a balanced approach to growing their money in the long term – and are comfortable with more ups and downs than with our Cautious Growth approach.
How we invest your money
Generally, with the Balanced growth approach, more of your money goes into higher risk investments with higher potential returns, and less goes into lower risks with lower potential returns.
Adventurous Growth Approach
Investment Mix
Who is it for?
For people looking for higher potential to grow their money in the long term – and willing to accept more ups and downs than with our Balanced Growth approach.
How we invest your money
Generally, with the adventurous growth approach,most of your money goes into higher risk investments with higher potential returns, and less goes into lower risks with lower potential returns.
Ready to go?
If you’re up to speed with our Stocks and Shares ISA and can’t wait to start your journey, let’s get going.