Could starting a Stocks & Shares ISA be my single best financial move ever?

Christopher Ruane explains why he thinks setting up a seemingly mundane Stocks and Shares ISA could turn out to be a financial masterstroke.

| More on:

The content of this article was relevant at the time of publishing. Circumstances change continuously and caution should therefore be exercised when relying upon any content contained within this article.

Young mixed-race couple sat on the beach looking out over the sea

Image source: Getty Images

You’re reading a free article with opinions that may differ from The Motley Fool’s Premium Investing Services. Become a Motley Fool member today to get instant access to our top analyst recommendations, in-depth research, investing resources, and more. Learn More.

Different people have their own lifetime best financial move. It might be starting a business, or spotting an unattributed Old Master in a provincial antique shop or auction house. What about the simple move of starting a Stocks and Shares ISA?

Perhaps, surprisingly, I think that could yet turn out to be the best financial move of a lifetime. Let me explain why.

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.

The power of long-term investment

Imagine I invested my annual Stocks and Shares ISA allowance of £20,000 each year for three decades.

That move alone would mean me putting aside £600,000. That is a significant amount!

By tucking it away in an ISA and investing it, I would be putting the money to work rather than frittering it away on daily treats from pricy drinks to posh meals.

But imagine something else. By investing it well, I could compound the value of my investment at 10% annually. Doing that, from a standing start today, my Stocks and Shares ISA could be worth over £3.6 million in 30 years!

That sounds like it could well be the financial move of a lifetime.

Four things to do

To get there, there are four things I would need to do. The first one is something I could do today – set up a Stocks and Shares ISA. There are lots of options available, so I would choose the one that best suited my own needs.

My second move would be coming up with the £20,000 annually to invest. Even if I could not manage that much, I would start with what I could, and try to build on that. I would still use the same investing approach, but if I invested less, my returns would be proportionately lower.

Thirdly, I would need to find shares to buy. I would keep my Stocks and Shares ISA diversified across a range of different shares. Finally, I would monitor my ISA over time to consider whether the investment case for any of my holdings had changed.

Finding shares to buy

In my example above, I discussed a 10% compound annual growth rate as an example. My Stocks and Shares ISA might do even better if I found shares like Alphabet (up 148% in five years) or London-listed Kainos (up 74% in five years).

Even a 10% annual return though, is harder to achieve over the long term than it may sound.

One share I hope might help me achieve that sort of return is M&G (LSE: MNG). It has the sorts of advantages I look for as a long-term investor, namely a large, enduring market, a strong brand, and a big existing customer base.

The company has grown its dividend annually in recent years and currently the dividend yield stands at 9.9%.

Since its 2019 listing though, the M&G share price has fallen 12%. So it has not delivered a 10% compound annual growth rate lately. I see ongoing risks, such as tight household budgets leading the asset manager’s customers to withdraw some funds, hurting profits.

But over time, I remain upbeat about the outlook for M&G. If I can buy the right companies for my Stocks and Shares ISA, I think it could end up being a boon for my personal finances.

Suzanne Frey, an executive at Alphabet, is a member of The Motley Fool’s board of directors. C Ruane has positions in M&g Plc. The Motley Fool UK has recommended Alphabet, Kainos Group Plc, and M&g Plc. Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool we believe that considering a diverse range of insights makes us better investors.

More on Investing Articles

ISA coins
Investing Articles

How much would you need in a Stocks & Shares ISA to target a £2,000 monthly passive income?

How big would a Stocks and Shares ISA have to be to throw off thousands of pounds in passive income…

Read more »

Middle-aged white man wearing glasses, staring into space over the top of his laptop in a coffee shop
Investing Articles

£10,000 invested in Diageo shares 4 years ago is now worth…

Harvey Jones has taken an absolute beating from his investment in Diageo shares but is still wrestling with the temptation…

Read more »

Investing Articles

Dividend-paying FTSE shares had a bumper 2025! What should we expect in 2026?

Mark Hartley identifies some of 2025's best dividend-focused FTSE shares and highlights where he thinks income investors should focus in…

Read more »

piggy bank, searching with binoculars
Dividend Shares

How long could it take to double the value of an ISA using dividend shares?

Jon Smith explains that increasing the value of an ISA over time doesn't depend on the amount invested, but rather…

Read more »

Businessman hand stacking money coins with virtual percentage icons
Investing Articles

£5,000 invested in Tesco shares 5 years ago is now worth this much…

Tesco share price growth has been just part of the total profit picture, but can our biggest supermarket handle the…

Read more »

Investing Articles

Here’s why I’m bullish on the FTSE 100 for 2026

There's every chance the FTSE 100 will set new record highs next year. In this article, our Foolish author takes…

Read more »

Thoughtful man using his phone while riding on a train and looking through the window
Growth Shares

UK interest rates fall again! Here’s why the Barclays share price could struggle

Jon Smith explains why the Bank of England's latest move today could spell trouble for the Barclays share price over…

Read more »

Man hanging in the balance over a log at seaside in Scotland
Investing Articles

2 out-of-favour FTSE 250 stocks set for a potential turnaround in 2026

These famous retail stocks from the FTSE 250 index have crashed in 2025. Here's why 2026 might turn out to…

Read more »