How to target big long-term wealth in a Stocks and Shares ISA

There are plenty of common mistakes investors make when building wealth in a Stocks and Shares ISA. Here’s how to avoid them.

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.

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.

A senior group of friends enjoying rowing on the River Derwent

Image source: Getty Images

British investors are exceptionally fortunate to have access to a Stocks and Shares ISA. This special type of investment account protects all profits generated from capital gains and dividends from the grubby fingers of HMRC.

And when a portfolio is left to compound without taxes taking a chunk of capital each year, it can have a profound impact on wealth.

Of course, having access to an investment ISA and using it correctly are two very different things. The stock market is far from risk-free. And tax-free gains are ultimately irrelevant if a portfolio moves in the wrong direction.

With that in mind, let’s explore how to execute a long-term investment strategy to try to build substantial wealth.

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.

Focus on the business, not the stock

In the short term, the movement of shares is driven by mood and momentum. When the market is optimistic, valuations rise. When things take a turn for the worse, prices tumble and may even crash in more extreme cases.

But in the long run, this volatility may be irrelevant since the performance of a stock is ultimately determined by the underlying business.

Don’t forget each share represents a piece of equity in a company. That makes shareholders owners in the underlying firm and therefore have a claim on any profits generated.

So when stock prices begin to drop, a common mistake is to sell as quickly as possible to minimise losses. Instead, investors should be investigating why valuations are falling.

Suppose a fundamental problem has emerged that breaks an investment thesis. In that case, selling, even at a loss, maybe the wiser move. But if the volatility is being created by a short-term hurdle, then this may actually be a buying opportunity.

This concept also works in reverse. If a firm’s valuation is skyrocketing, investors typically start buying more in fear of missing out. But if the strong upward trajectory is being fuelled by unrealistic expectations of future performance, then it could be wise to cash out.

Risk vs reward

Executed poorly, an investment strategy can spectacularly backfire. And investors may be left with far less wealth than when they started.

But taking a patient and disciplined approach can propel a Stocks and Shares ISA to impressive heights. And by employing simple tactics like diversification and pound-cost averaging, it’s possible to keep risk in check at the same time.

Let’s say an investor only manages to match the FTSE 100’s average 8% gains in the long run. That’s still enough to reach millionaire territory within three decades when investing £500 each month in an ISA, not having to worry about taxes.

Meanwhile, this timeline can be significantly shorter for the investors who manage to achieve market-beating returns, even if it’s just by an extra 1%.

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

Man writing 'now' having crossed out 'later', 'tomorrow' and 'next week'
Investing Articles

The best time to buy stocks? It might be right now

Short-term issues that delay long-term trends create opportunities to buy stocks. And that could be happening right now with a…

Read more »

Queen Street, one of Cardiff's main shopping streets, busy with Saturday shoppers.
Investing Articles

Here’s why Next stock rose 5% and topped the FTSE 100 today

Next was the leading FTSE 100 stock today, rising 5%. Our writer takes a look at why and asks if…

Read more »

Renewable energies concept collage
Investing Articles

Up 458% in a year, could the Ceres Power share price go even higher?

Christopher Ruane reviews some highs and lows of the Ceres Power share price over the years and wonders whether the…

Read more »

Rolls-Royce's Pearl 10X engine series
Investing Articles

Are the glory days over for Rolls-Royce shares?

Rolls-Royce shares have soared in recent years. Lately, though, they have taken a tumble. Could there be worse still to…

Read more »

Group of friends meet up in a pub
Investing Articles

Are ‘66% off’ Diageo shares a once-in-a-decade opportunity?

Diageo shares have taken another hit in the early weeks of 2026. Are we looking at a massive bargain or…

Read more »

Investing Articles

Meet the UK stock under £1.50 smashing Rolls-Royce shares over the past year

While Rolls-Royce shares get all the attention, this under-the-radar trust has quietly made investors a fortune. But is it still…

Read more »

UK financial background: share prices and stock graph overlaid on an image of the Union Jack
Investing Articles

Down 19%, the red lights are flashing for Barclays shares!

Barclays shares have fallen almost a fifth in value as the Middle East war has intensified. Royston Wild argues that…

Read more »

Aviva logo on glass meeting room door
Investing Articles

After falling another 5%, are Aviva shares too cheap to ignore?

£10,000 invested in Aviva shares five years ago would have grown 50% by now. But what might the future hold,…

Read more »