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.

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

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.

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

Close-up of a woman holding modern polymer ten, twenty and fifty pound notes.
Investing Articles

£20,000 in savings? Here’s how someone could aim to turn that into a £10,958 annual second income!

Earning a second income doesn't necessarily mean doing more work. Christopher Ruane highlights one long-term approach based on owning dividend…

Read more »

Road 2025 to 2032 new year direction concept
Investing Articles

My favourite FTSE value stock falls another 6% on today’s results – should I buy more?

Harvey Jones highlights a FTSE 100 value stock that he used to consider boring, but has been surprisingly volatile lately.…

Read more »

UK supporters with flag
Investing Articles

See what £10,000 invested in the FTSE 100 at the start of 2025 is worth today…

Harvey Jones is thrilled by the stunning performance of the FTSE 100, but says he's having a lot more fun…

Read more »

Investing Articles

Prediction: here’s where the latest forecasts show the Vodafone share price going next

With the Vodafone turnaround strategy progressing, strong cash flow forecasts could be the key share price driver for the next…

Read more »

Front view of a young couple walking down terraced Street in Whitley Bay in the north-east of England they are heading into the town centre and deciding which shops to go to they are also holding hands and carrying bags over their shoulders.
Investing Articles

How much do you need in a SIPP or ISA to aim for a £2,500 monthly pension income?

Harvey Jones says many investors overlook the value of a SIPP in building a second income for later life, and…

Read more »

Friends at the bay near the village of Diabaig on the side of Loch Torridon in Wester Ross, Scotland. They are taking a break from their bike ride to relax and chat. They are laughing together.
Investing Articles

Can you turn your Stocks and Shares ISA into a lean, mean passive income machine?

Harvey Jones shows investors how they can use their Stocks and Shares ISA to generate high, rising and reliable dividends…

Read more »

Close-up image depicting a woman in her 70s taking British bank notes from her colourful leather wallet.
Investing Articles

Move over Lloyds, are Barclays shares the ones to go for in 2026?

As we head into 2026 with inflation and interest rates set to fall, what does the banking outlook offer for…

Read more »

Young Black man sat in front of laptop while wearing headphones
Investing Articles

Down 60% with a 10.2% yield and P/E of 13.5! Is this FTSE 250 stock a once-in-a-decade bargain? 

Harvey Jones is dazzled by the yield available from this FTSE 250 company, and wonders if it's the kind of…

Read more »