Here’s why I’d invest £500 a month in cheap FTSE 100 stocks in an ISA starting today

Investing regularly in FTSE 100 (INDEXFTSE:UKX) shares could improve your long-term financial outlook despite short-term risks, in Peter Stephens’ opinion.

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 £500, or any other amount, in FTSE 100 shares on a regular basis could prove to be a profitable move over the long run. The index currently contains many companies that appear to be trading at attractive prices. Over time, they could deliver strong recoveries from their current lows, which improves your financial outlook.

Of course, there are risks ahead in the short run. But, through persisting with a regular investing strategy, you could benefit from the FTSE 100’s likely outperformance of other assets. Especially when using a tax-efficient account such as an ISA.

Long-term growth potential

Regularly investing in the FTSE 100 since its inception in 1984 would have been a highly profitable strategy. The index has risen from 1,000 points to around 6,000 points. It’s also produced strong dividend growth in that time.

As such, a monthly investment of £500 since the index’s inception would now be worth around £1.1m. During that time, of course, there have been many challenging periods for the FTSE 100. For example, it has experienced recessions, market crashes, and periods where other assets, such as buy-to-let properties, have appeared to be more attractive.

Despite its challenges, the FTSE 100 has made strong gains since its inception. Even though the current difficulties brought about by coronavirus may cause further declines in its price level in the short run, the index is very likely to produce impressive long-term growth. Therefore, buying large-cap shares regularly could allow you to take advantage of its recovery potential.

Relative appeal

Investing £500 per month in other assets is unlikely to deliver a return that’s as attractive as the FTSE 100. The key reason for this is that other mainstream assets, such as Cash ISAs and investment-grade bonds, currently offer exceptionally low returns. That’s due to interest rates being at historic lows.

For example, many Cash ISAs offer income returns that are 1.5%, or below. Assuming a 1.5% annual return on a £500 investment over the same 36 years of the FTSE 100’s existence would lead to a total valuation of £283,000. Although this is still a significant sum of money, it’s far lower than the gains delivered by the FTSE 100 over the same period.

FTSE 100 accessibility

Furthermore, the FTSE 100 is easy for many investors to access. Opening a tax-efficient Stocks and Shares ISA is cost-effective and can be completed in a matter of minutes online. This compares favourably to undertaking a buy-to-let property. This requires a large initial deposit, finance and legal costs. And, with the FTSE 100 offering a large amount of diversity, it may be a lower-risk opportunity than buying a small number of properties.

Therefore, while the FTSE 100’s future returns may, or may not, match those of its past, the index’s low price level suggests that it can produce impressive capital growth. As such, now could be the right time to start investing regularly in large-cap shares to boost your financial prospects.

Peter Stephens has no position in any of the shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. 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

DIVIDEND YIELD text written on a notebook with chart
Investing Articles

How big does an ISA need to be to aim for a £1,500 monthly second income?

Harvey Jones shows how building a balanced portfolio of FTSE 100 dividend stocks can produce a high-and-rising second income in…

Read more »

Person holding magnifying glass over important document, reading the small print
Investing Articles

£20,000 invested in BP shares 1 year ago is now worth…

BP shares have rocketed in the past 12 months, yet analysts think the real growth story is only just beginning,…

Read more »

A pastel colored growing graph with rising rocket.
Investing Articles

A 6.8% forecast yield! 1 often-overlooked FTSE 100 income stock to buy today?

This income stock offers a high forecast yield and strengthening momentum, yet many investors overlook it — creating a rare…

Read more »

GSK scientist holding lab syringe
Investing Articles

GSK’s share price is under £22, but with a ‘fair value’ much higher, is it time for me to buy more right now? 

GSK’s share price rose over the last year, but a huge gap remains between its price and fair value —…

Read more »

Businessman hand stacking money coins with virtual percentage icons
Investing Articles

Here’s how investors can aim for £11,363 a year in passive income from £20,000 in this overlooked FTSE media gem

I think this media stock is commonly overlooked by investors looking for high passive income, but it shouldn’t be, given…

Read more »

Tesla car at super charger station
Investing Articles

Why is Tesla stock down 30% since late 2025?

Tesla stock has been a bit of a car crash in 2026. Edward Sheldon looks at what’s going on, and…

Read more »

UK supporters with flag
Investing Articles

Is Wise now the UK stock market’s top growth share?

Wise rose around 4% in the UK stock market yesterday, bringing its four-year gain to 135%. Why are investors warming…

Read more »

Warhammer World gathering
Investing Articles

£20,000 invested in this FTSE 100 stock 10 years ago is now worth this astonishing amount…

This FTSE 100 stock's delivered an amazing return over the past 10 years. James Beard considers whether it’s worth holding…

Read more »