Aiming for £1m? Start investing regularly with a Stocks and Shares ISA

Consistently drip-feeding £500 each month into a Stocks and Shares ISA can help investors build a £1m portfolio in the long run.

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.

Couple working from home while daughter watches video on smartphone with headphones on

Image source: Getty Images

By leveraging the power of compounding, regular investment and a Stocks and Shares ISA, it’s possible for investors to start building a fairly sizable nest egg. And when given enough time and capital, an individual’s net worth could even be pushed into millionaire territory. Here’s how.

The power of an ISA

The miracle of compounding is well known. By earning interest on top of interest, whether it be from dividends or capital gains, a snowball effect follows. And after a few decades, a seemingly small monthly contribution of a couple hundred pounds can turn into a seven-figure portfolio.

However, an expense many investors often end up overlooking is taxes. Just like income, HRMC demands its pound of flesh from investors. And while there are some clever tricks to reduce capital gains tax, this handicap can significantly slow down the wealth-building process. That’s why a Stocks and Shares ISA is so powerful.

While investors can only add up to £20,000 a year within an ISA, any capital gains or dividends received are completely tax-free. And while a few fortunate individuals have the ability to maximise their ISA allowance, most investors never reach this limit. But they don’t have to.

Investing £500 a month equates to just £6,000 a year – 30% of the annual allowance. And assuming an investor matches the FTSE 250’s 11% historical average return, that’s enough to build a £1m ISA in just over 27 years when starting from scratch. Needless to say, that’s quite a chunky tax-free retirement fund and could drastically improve the quality of life for most pensioners.

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.

Risk and expectations

Achieving an average annualised 11% return on paper sounds easy. But in practice, it can be a challenge. It may seem obvious to just invest in a low-cost FTSE 250 index fund to replicate these gains moving forward. However, there’s no guarantee the index will continue growing at this pace over the next three decades. Consequently, investors could have far less than expected in 2051.

Assuming the UK’s mid-cap index doesn’t continue delivering double-digit gains, investors could be better served pursuing a stock-picking strategy. This approach is riskier. It demands more time, knowledge, and temperament that not everyone has. Yet it also opens the door to potentially market-beating returns.

Even if an investor were to boost their average return to just 12%, that would add an additional £200,000 to their ISA over the same period. Of course, a poorly constructed or managed portfolio could easily move in the opposite direction. And investors may end up destroying wealth, not creating it.

That’s why it’s paramount to carefully research and analyse individual stocks diligently and carefully consider the value they can bring to an overall portfolio.

There’s no denying this is a time-consuming process. However, given the potential rewards, it’s one I feel is worth pursuing, especially since services like Share Advisor can help investors execute a stock-picking strategy.

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

Stack of one pound coins falling over
Investing Articles

Want to turn your ISA into a passive income machine? These 3 steps help

Christopher Ruane looks at a trio of factors he reckons could help an investor as they aim to earn passive…

Read more »

Investing For Beginners

2 FTSE shares that have been oversold in this stock market correction

Jon Smith reviews the recent market slump and points out a couple of FTSE shares he believes have been oversold…

Read more »

Warren Buffett at a Berkshire Hathaway AGM
Investing Articles

As the stock market moves down, I’m taking the Warren Buffett approach!

Rather than getting nervous as markets move around, our writer is looking to the career of Warren Buffett to see…

Read more »

Fans of Warren Buffett taking his photo
Investing Articles

Here’s how a stock market crash could be brilliant news for your retirement!

This writer isn't peering into a crystal ball trying to time the next stock market crash. Instead, he's making an…

Read more »

Burst your bubble thumbtack and balloon background
Investing Articles

Down 93%, should I load up on this penny stock while it’s under 1p?

The small-cap company behind this penny stock is eyeing up a substantial global market opportunity. So why did it crash…

Read more »

Portrait of pensive bearded senior looking on screen of laptop sitting at table with coffee cup.
Investing Articles

Is Fundsmith Equity still worth holding in a Stocks and Shares ISA or SIPP in 2026?

The performance of the Fundsmith Equity fund has been shocking over the last two years. Is it still smart to…

Read more »

Young female hand showing five fingers.
Investing Articles

5 smart moves to make before the 2025/2026 ISA deadline

Taking advantage of the annual allowance isn’t the only smart move to make before the upcoming ISA deadline, says Edward…

Read more »

Businesswoman calculating finances in an office
Investing Articles

Here’s the dividend forecast for Lloyds shares through to 2028

Can dividend forecasts tell investors much about the outlook for banking shares? Stephen Wright sets out what investors really need…

Read more »