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Stocks & Shares ISA Calculator

Project the growth of your Stocks and Shares ISA and compare with Cash ISA returns over time.

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Investment Details

£
£

Past performance does not guarantee future results. The value of investments can go down as well as up.

Projected Growth

Stocks & Shares ISA Value

£458,000

After 20 years

Total Contributed

£205,000

Investment Growth

£253,000

Advantage over Cash

£137,353

Stocks & Shares ISA

£458,000

Growth: £253,000

Cash ISA

£320,648

Growth: £115,648

Year-by-Year Breakdown

YearContributedS&S ISACash ISA
1£15,000£16,050£15,600
2£25,000£27,874£26,624
3£35,000£40,525£38,089
4£45,000£54,061£50,013
5£55,000£68,546£62,413
10£105,000£157,672£132,265
15£155,000£282,676£217,250
18£185,000£380,689£276,841
19£195,000£418,038£298,315
20£205,000£458,000£320,648
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Understanding Stocks & Shares ISAs

A Stocks and Shares ISA allows you to invest in a wide range of assets including funds, shares, bonds, and investment trusts, all within a tax-efficient wrapper. Any income (dividends) and capital gains earned within the ISA are completely free from UK tax, making it one of the most powerful savings tools available to UK investors. At Calculator Site, we built this tool to help you see the potential of long-term investing.

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Risk and Time Horizon

Investing in a Stocks and Shares ISA carries more risk than a Cash ISA, as the value of your investments can fall as well as rise. However, historically, equities have outperformed cash over periods of 10 years or more. The general guidance is to invest for at least 5 years to give your investments time to recover from any short-term market downturns. For a broader view of your finances, try the Take-Home Pay Calculator.

The Power of Compounding

The key advantage of investing is the potential for compound growth. While cash savings earn a fixed interest rate, investments can grow through both capital appreciation and reinvested dividends. Over 20 or 30 years, this compounding effect can result in significantly larger returns.

£20,000

Annual ISA Allowance

7-10%

Historical Annual Return

5+ Years

Recommended Horizon

Our Compound Interest Calculator can help you visualize this effect. You might also find our Savings Calculator useful.

How to use this Calculator Site tool

Enter an initial investment, your planned annual contribution, an expected return rate, and the number of years you plan to invest. The  calculator will project the future value of your Stocks and Shares ISA and compare it against a standard Cash ISA. The year-by-year breakdown shows how your investment grows over time, illustrating the power of compounding. For official ISA rules, visit GOV.UK ISA guide.

Frequently Asked Questions

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