Is a Stocks and Shares ISA worth it? The Chancellor’s recent moves might have quietly answered the question for you.
Cash ISAs are getting less generous. And that makes it a good time to check out the alternatives.
The £8,000 question
From April 2027, the ISA situation is changing. The tax advantages and overall £20,000 annual limit survive, but for under-65s, only £12,000 of it will be usable for cash.
Please note that tax treatment depends on the individual circumstances of each client and may be subject to change in future. The content in this article is provided for information purposes only. It is not intended to be, neither does it constitute, any form of tax advice. Readers are responsible for carrying out their own due diligence and for obtaining professional advice before making any investment decisions.
By contrast, the Stocks and Shares ISA retains the full £20,000 limit. But there’s a catch in the small print that demands attention.
From the same date, uninvested cash in a Stocks and Shares ISA attracts a 22% charge (not tax) on its interest. The message isn’t subtle – the government wants that money invested.
What £10,000 might become
Past returns never guarantee future ones – if they did, investing would be easy. But history offers a benchmark for £20,000 left alone for a decade:
| Annual Return | Basis | 2036 Value |
|---|---|---|
| 4.5% | Competitive Cash ISA rate | £31,060 |
| 6.4% | FTSE 100, 20-year annualised total return | £37,192 |
| 10.6% | S&P 500, 100-year average | £54,774 |
Mind the gap, as they say. At cash rates, £20,000 gains about £11,000 in 10 years. At the S&P 500’s long-run average, it nearly triples.
That’s not based on deep insight about which stocks to buy. It’s just the effect of compound interest, uninterrupted, with dividends reinvested.
What to invest in?
So a stocks and shares ISA, full invested, is clearly the way to go. Within an ISA, I think Microsoft (NASDAQ: MSFT) is a candidate for those just getting started to think about buying.
It’s one of the best-known businesses on the US stock market, but sometimes opportunities are hiding in plain sight.
The idea is simple: it’s perhaps the best-positioned large company for artificial intelligence (AI) growth. Azure – its cloud computing division – grew 40% in constant currency last quarter.
On top of this, Microsoft’s AI business has hit a $37bn annual run-rate, up 123% year on year. In other words, AI is driving growth.
The stock, however, is down 17% since the start of the year because investors are worried about the associated risks. These are real, but they’re worth a closer look.
What’s the risk?
Microsoft plans to spend roughly $190bn in 2026 on AI infrastructure. And some $25bn of that is just higher memory prices, rather than excess capacity.
As a result, gross margins are at their narrowest levels since 2022. That happens with investments, but if AI demand falters – for whatever reason – much of that outlay is likely to be written off.
The risk is real, but I think it’s also manageable. The potential damage looks to me like short-term disruption, not an existential threat.
Microsoft is one of only two US companies with a credit rating of AAA. So at the very least, I think it’s in a better position to make this kind of investment than any other business.
My verdict
Stocks and Shares ISAs don’t come with guarantees. But they have the potential to turn £20,000 into £54,774 within a decade.
Cash doesn’t. And with its tax shelter shrinking from next April, I think the odds favour investing over saving.
The World Cup feels like a good time to start keeping score. And with Microsoft’s software unit growing earnings per share at 23%, I think it’s a good name to consider starting with.
Should you invest £5,000 in Microsoft right now?
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And right now, Mark thinks there are 6 standout stocks that investors should consider buying. Want to see if Microsoft made the list?
Stephen Wright owns shares in Microsoft.
