Here’s how I’d invest £20k in UK shares today to double my money

I think investing £20k in UK shares could produce 100% returns over the long run. Here’s how I’d achieve that goal in today’s stock market.

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.

Investing £20k in UK shares today could realistically produce a portfolio valued at £40k within nine years. After all, the FTSE 100 and FTSE 250 have delivered annual total returns of around 8% in the past 20 years. Assuming the same rate of return in future would mean 100% returns are achieved within nine years.

However, it may be possible to beat the stock market’s returns. Many shares are trading at cheap prices that seem to undervalue their long-term growth prospects. Through buying a diverse range of them, an investor could reduce the amount of time it takes to double their money on the stock market.

Investing £20k in UK shares trading at cheap prices

Despite the recent stock market rally, it’s possible to invest £20k in UK shares that trade at cheap prices. Investor sentiment towards a wide range of sectors remains downbeat, with their challenging near-term prospects weighing on valuations.

For example, financial services companies including Aviva and HSBC trade significantly lower than they did at the start of the year. Yet, they have revised strategies that could lead to improving profitability over the long run.

Buying cheap shares has historically been a sound means of generating market-beating returns. For example, investors who purchased FTSE 100 and FTSE 250 shares after the global financial crisis are likely to have benefitted from the stock market’s subsequent recovery.

Similarly, the same approach is likely to have been successful after other notable bear markets, such as the 1987 crash and dot com bubble.

Buying high-quality businesses from across the FTSE 100 and FTSE 250

Clearly, investing £20k in UK shares comes with risks. The economic outlook is uncertain, and could even get worse before it improves. As such, buying a diverse range of companies is perhaps more important than ever.

A broad range of shares in a portfolio means less reliance on a small number of sectors for returns. Over time, this can have a positive impact on an investor’s chances of doubling their money.

Meanwhile, buying high-quality companies could be an important means of outperforming the stock market. Clearly, what makes a business ‘high quality’ is subjective. However, traits such as a solid balance sheet, a wide economic moat and a strategy that provides flexibility in an uncertain economic period are likely to be key ingredients.

Such companies may outperform the stock market – especially when they trade at cheap prices today following the recent stock market crash.

Making 100% over and over again

Of course, investing £20k in UK shares to make a 100% return can lead to a surprisingly large portfolio in the long run. Compounding makes each subsequent 100% return even more valuable in monetary terms.

Even assuming an 8% annual return would mean an investor with a 36-year timeframe has sufficient time for their initial investment to double four times. In doing so, a £20k investment could ultimately be worth £320k.

As such, taking a long-term view and buying high-quality companies at cheap prices could be a sound move.

Peter Stephens owns shares of Aviva and HSBC Holdings. The Motley Fool UK has recommended HSBC Holdings. 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

British pound data
Investing Articles

The red lights are flashing again for Lloyds’ share price! Here’s why

Lloyds' share price continues to defy gravity. But Royston Wild thinks it's only a matter of time before the FTSE…

Read more »

Aston Martin DBX - rear pic of trunk
Investing Articles

Aston Martin shares are now only 41p!

Aston Martin shares just dropped to around the 41p mark! Is this a brilliant buying opportunity or a stock that…

Read more »

Artillery rocket system aimed to the sky and soldiers at sunset.
Investing Articles

Up 325% in 5 years! But are BAE System shares still a no-brainer buy?

BAE Systems shares would have been a brilliant buy five years ago. But could they still offer excellent returns if…

Read more »

Investing Articles

How much do you need to invest each month into FTSE 100 shares to aim for a million?

Simply by putting a few hundred pounds a month into FTSE 100 shares, how might someone aim to become a…

Read more »

Close-up as a woman counts out modern British banknotes.
Investing Articles

£10,000 invested in BAE shares at the beginning of 2026 is now worth…

Paul Summers tips his hat to those who invested in BAE Systems shares when markets opened back up in January.…

Read more »

A senior man and his wife holding hands walking up a hill on a footpath looking away from the camera at the view. The fishing village of Polperro is behind them.
Investing Articles

What size ISA do you need for £250-a-week retirement income?

Harvey Jones outlines the advantages of investing in a Stocks and Shares ISA rather than leaving money in cash, and…

Read more »

Mature Caucasian woman sat at a table with coffee and laptop while making notes on paper
Investing Articles

£5,000 invested in Legal & General shares 5 years ago is now worth…

Harvey Jones crunches the numbers to show how much an investor would have earned from Legal & General shares lately,…

Read more »

Investing Articles

Just check out the latest bumper forecasts for Lloyds, NatWest and Barclays shares

Harvey Jones says Barclays shares have had a terrific year and there could be more action to come. So what's…

Read more »