What is a Stocks and Shares ISA?
A Stocks and Shares ISA is a tax wrapper authorised by HMRC that lets you buy shares, funds, and ETFs with no UK tax on dividends, no tax on interest, and no capital gains tax on growth. Anyone aged 18 or over and UK-resident can open one. The allowance is £20,000 per tax year (2024-25), and the year resets every 6 April. You can split the allowance across multiple ISA types (cash, S&S, innovative finance, LISA), but the total stays £20,000. Provider charges and fund OCFs still apply, but HMRC takes nothing.
Put £500 a month into a global index fund inside a S&S ISA from age 25 to 60. At ~8% long-run nominal returns (broadly in line with MSCI World), you have contributed £210,000 of your own money and the pot is around £1.05m. Every penny of growth and every dividend along the way is outside the tax net. The same money in a general investment account would have paid tax on dividends above the £500 allowance and CGT on disposals above £3,000.
Holding cash inside a Stocks and Shares ISA ‘until markets calm down’. You are wasting the wrapper. Cash earns interest that was already tax-free up to your Personal Savings Allowance, so the ISA shield is worthless on it. Either invest it or move it to a Cash ISA.
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