How I’d invest to make a £1m in a Stocks and Shares ISA

A Stocks and Shares ISA worth £1m is perfectly possible, says Tom Rodgers. But without this key element you won’t succeed.

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.

Stocks and Shares ISA success doesn’t come for free. But it might be a lot cheaper than you think.

Whether you started at 20, just got going at 30, or still haven’t made your first purchase at 40, it doesn’t really matter.

The only things you need are regular commitment and time.

Why? Well, over the course of 35 years, from 1984 to 2019, the FTSE 100 returned an average 7.75% per year.

Take your time

Promises of immediate riches at zero risk are confined to scams designed to cheat you out of your money. You will have to take some risk: you do have to invest money to make money.

But if you invest over a long enough time frame, you can certainly reduce your risk and keep more of your money.

Investing the same amount in a Stocks and Shares ISA every month does two things.

Firstly, it allows you to ‘pound-cost average’. This means you take advantage of cheaper prices when the market is down and smooths out your returns over time. It also makes sure you don’t just buy in a lump sum when the stock market could be well overvalued.

Secondly, it builds up compound gains. The longer you can keep investing, the more compound interest works in your favour.

For example, say you start with a healthy £10,000 lump sum. Buy a single FTSE 100 tracker and let it sit in your Stocks and Shares ISA. If you add nothing to this £10,000 over 35 years, you end up with £136,664, at the average 7.75% a year return.

But add £500 a month and that £136,664 suddenly turns into £1,154,996! Compound interest becomes exponentially more powerful the more we can add to our original stake over time.

Sticking with a lump sum is like powering an engine with coal. But adding extra money every month is like injecting it with rocket fuel!

Reinvest

Each scrap of cash you can put together in a Stocks and Shares ISA should be working to make you richer.

And history has shown us that investors make their most money over time from reinvesting dividends. Without this key fact, you lose the ability to take advantage of compounding.

At first, the impact from reinvesting dividends is quite small. Not much will happen for the first 10 to 15 years: a long time to see no huge growth! But after 15 years, your wealth really starts to motor.

Think of an exponential curve. It starts small, and increases slowly. Then suddenly it starts to increase rapidly, and shoots ever higher each year after that.

The additional impact every year from ever greater numbers starts to hit a critical mass at about year 18. If you can be patient and hold on, this is where you’ll make your £1m.

Stocks and Shares ISA success

The best thing about a Stocks and Shares ISA is that all your gains are tax-free. You don’t have to give the government a slice of your earnings from share price rises or dividends, and it will never cost you anything to take money out.

Following the simple principle of adding £500 a month and staying consistent over time. That’s how I plan to make £1m in my Stocks and Shares ISA, and I think you can too.

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 British bank notes
Investing Articles

£9,000 in savings? Here’s how to try and turn that into a £193 monthly second income

With a long-term approach and applying basic principles of good investment, our writer reckons someone with under £10k could earn…

Read more »

Investing Articles

A 2026 stock market crash could be a rare passive income opportunity

If a stock market crash comes our way then it might throw up plentiful opportunities for investors to secure a…

Read more »

Tesla car at super charger station
Investing Articles

£10,000 invested in Tesla stock 1 year ago is now worth…

Dr James Fox takes a closer look at Tesla stock with the incredibly volatile mega-cap company surging and pulling back…

Read more »

British pound data
Investing Articles

My personal warning for anyone tempted by the plunging Aston Martin share price

Harvey Jones was so captivated by the plunging Aston Martin share price that he ignored an old piece of investment…

Read more »

Stacks of coins
Investing Articles

This penny share just crashed 13% to 19p! Time to buy?

After another fall today, this penny stock has now crashed 70% since April 2021. Is it one that should be…

Read more »

Trader on video call from his home office
Investing Articles

Down 19%! Here’s why Barclays shares look a serious bargain to me right now

Barclays shares have slumped recently, but a big gap between price and fair value has opened, offering nimble long-term investors…

Read more »

CEO Mark Zuckerberg at F8 2019 event
Investing Articles

Why Meta Platforms shares fell 12.5% in March

Historically, investors have done well by buying Meta Platforms shares when the price has fallen. But is the latest legal…

Read more »

Arrow symbol glowing amid black arrow symbols on black background.
Investing Articles

£20,000 invested in BAE Systems shares 4 years ago is now worth…

BAE Systems' shares have soared since 2022, yet rising NATO budgets are just starting to feed through, so the real…

Read more »