How much could an ISA investor make putting £700 a month into growth stocks?

This writer shows how a relatively modest sum of money invested each month into growth stocks can result in a sizeable portfolio.

| More on:

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.

Young mixed-race woman jumping for joy in a park with confetti falling around her

Image source: Getty Images

Many people start their investing journey by putting money into growth stocks. This is entirely understandable, as shares that grow much quicker than the average obviously have the potential to build significant wealth over time.

Additionally, some growth stocks have famously delivered spectacular returns. AI chip maker Nvidia, for example, has skyrocketed 2,180% over five years and 20,470% across a decade!

Here, I want to consider how large a Stocks and Shares ISA portfolio could be after years of investing £700 a month into growth firms.

What are they?

Growth stocks are simply shares of companies that are growing much faster than the market average or their peers. If a listed business is consistently growing its annual revenue above 25% say, then it would normally be defined as a growth share.

Often, these stocks will be from the technology sector, but not always. Look at engine maker Rolls-Royce, which is now putting up very strong revenue and earnings growth in the double digits. The FTSE 100 blue-chip stock’s up 750% in three years!

Clearly then, growth firms can come in many guises, offering various avenues of growth for an ISA portfolio.

A cautionary tale

However, growth investing is certainly not without risk. Companies than can keep increasing their revenue and/or earnings in the double digits for long periods are rare beasts. As a result, many stocks that appear to be the real deal turn out not to be.

I’ve owned a handful over the years. One that sticks in my memory is Illumina (NASDAQ: ILMN). Shares of this gene-sequencing giant soared for many years, then started slumping as growth tailed off.

The stock’s down 83% since August 2021.

Illumina hasn’t done itself any favours in recent years. For example, it acquired biotech firm Grail in 2021 without securing the necessary regulatory approvals, which resulted in financial penalties, strategic setbacks, and a forced divestiture. Oops. 

Today, the US firm is under new management and is trying to reignite the growth engine. Perhaps it will bounce back.

However, it was recently put on China’s ‘unreliable entity’ list of foreign firms. So it could face fines and restrictions in a long-term growth market that represents 7% of revenue. Not ideal.

Fortunately, I managed to sell my Illumina holding in 2022 before most of the share price damage was done. But it serves as a cautionary tale of what can go wrong and why companies need to be monitored closely.

How much?

The key to minimising such risks is to build a diverse portfolio. Despite disappointments like Illumina, my portfolio has benefitted from growth stocks such as Axon Enterprise, Intuitive Surgical, MercadoLibre, Shopify, and Games Workshop. All have been market-beaters.

There’s no specific rule on the number of stocks to own. But I would say 20-30 holdings is a good target, certainly for new investors.

Through such diversification, I reckon an 11% average return is achievable long term. That’s not guaranteed though, as it’s above the market average. But with sound stock research and consistency, such a return is not beyond the realms of possibility.

With this rate of return, someone investing £700 a month would go on to build a £1m ISA portfolio after 25 years. Starting from scratch, that would be some achievement.

Ben McPoland has positions in Axon Enterprise, Games Workshop Group Plc, Intuitive Surgical, MercadoLibre, Rolls-Royce Plc, and Shopify. The Motley Fool UK has recommended Axon Enterprise, Games Workshop Group Plc, Intuitive Surgical, MercadoLibre, Nvidia, Rolls-Royce Plc, and Shopify. 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

Two employees sat at desk welcoming customer to a Tesla car showroom
Investing Articles

Tesla stock’s down 19% this year. Time to buy?

Tesla stock has tumbled almost a fifth in less than three months. But the company has proven its mettle before.…

Read more »

piggy bank, searching with binoculars
Dividend Shares

How to turn a stock market correction into a £10k passive income

Jon Smith points out why the stock market correction could provide a great opportunity to start building a dividend portfolio,…

Read more »

Smiling white woman holding iPhone with Airpods in ear
Investing Articles

These legendary growth stocks are down 40% or more. Time to consider buying?

History shows that buying high-quality growth stocks when they’re well off their highs can be financially rewarding in the long…

Read more »

Portrait Of Senior Couple Climbing Hill On Hike Through Countryside In Lake District UK Together
Investing Articles

Is it worth investing in a SIPP in 2026?

Ben McPoland highlights a high-quality FTSE 100 stock that he thinks is worth considering as part of a SIPP portfolio…

Read more »

A rear view of a female in a bright yellow coat walking along the historic street known as The Shambles in York, UK which is a popular tourist destination in this Yorkshire city.
Investing Articles

£5,000 invested in Greggs shares 10 days ago is now worth…

After falling yet again in March, are Greggs shares really worth the hassle today? Ben McPoland takes a look at…

Read more »

Rear view image depicting a senior man in his 70s sitting on a bench leading down to the iconic Seven Sisters cliffs on the coastline of East Sussex, UK. The man is wearing casual clothing - blue denim jeans, a red checked shirt, navy blue gilet. The man is having a rest from hiking and his hiking pole is leaning up against the bench.
Investing Articles

With a spare £380, here’s how someone could start investing before April!

Can someone start investing fast with a spare few hundred pounds? Our writer explains how they could -- and some…

Read more »

Renewable energies concept collage
Investing Articles

Here’s a top dividend share to consider buying for your ISA right now

Looking for dividend shares to tuck away in a long-term Stocks and Shares ISA? This trust is offering one of…

Read more »

Close-up of British bank notes
Investing Articles

Is this a once-in-a-decade chance to buy this top passive income stock cheaply?

When's the best time to consider buying passive income stocks? When share prices are down and dividend yields are up,…

Read more »