£20,000 Stocks and Shares ISA: how long would it take to reach £1 million?

This writer considers how long it would take an investor to reach a seven-figure sum by maxing out their Stocks and Shares ISA every year.

| 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.

Thoughtful man using his phone while riding on a train and looking through the window

Image source: Getty Images

The Stocks and Shares ISA is a truly wonderful thing. Through one of these beauties, UK investors can build wealth without worrying about tax obligations.

Whatever returns are made are theirs to keep, with the contribution limit set at a generous £20k a year.

But how long could it realistically take to become an ISA millionaire? Let’s take a look.

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.

Powerful wealth-building vehicle

Boiling it down, the two key things are the amount contributed and the return on investment.

In other words, someone generating a 7% average annual return on a yearly investment of £5,000 is going to have to wait a lot longer than another achieving 10% on £20,000 invested every year.

For the former, it would take about four decades to reach £1m, whereas the person maxing out the full contribution limit each year would get there in just 19 years.

Indeed, the difference is so stark that the £20k-a-year ISA investor generating a 10% return would see the value of their portfolio rise above £8m after 40 years!

I should mention that these calculations assume that dividends are retained rather than spent. Ideally, they should be reinvested to fuel the compounding process.

I also haven’t factored in platform fees, which are a real cost that needs to be accounted for (they differ with each provider).

Still, the wealth-creating potential of the ISA is incredibly powerful for everyday investors. Reminding myself of this keeps me motivated to invest regularly.

Which stocks to buy?

There isn’t one single investing style to build wealth in the stock market.

Warren Buffett, for example, built an empire investing in businesses that he understood well. He looked for a margin of safety with the valuation, sticking to established and profitable companies with long track records.

As Buffett memorably put it, “It’s far better to buy a wonderful company at a fair price than a fair company at a wonderful price”. Buying an average company at a high price is a recipe for poor returns in the stock market.

Many other investors have made fortunes taking on more risk by investing in disruptive growth companies. Think Netflix as streaming started taking off 15 years ago, or Tesla in 2012 before electric vehicles went mainstream.

The Goldilocks zone

Arguably, the sweet spot is finding a wonderful company with strong growth prospects that is trading at an attractive valuation.

One potential example I see at the moment is Novo Nordisk (NYSE: NVO). This healthcare giant is a leader in diabetes and GLP-1 weight-loss treatments through brands like Ozempic and Wegovy.

The stock is down a whopping 54% since September!

The reason is that Novo Nordisk has fallen behind arch-rival Eli Lilly in the race to develop a GLP-1 pill (Wegovy is currently an injectable medication). So there’s a risk the company is losing its leading market position in this lucrative space.

Yet Novo Nordisk is still expected to grow strongly over the next few years, according to most analysts. And the global weight-loss market is projected to exceed $150bn in future — far too big to be dominated by any one company.

Meanwhile, the stock is trading at just under 14 times next year’s forecast earnings, and offering a 2.5% dividend yield. At $65, I really like the risk/reward setup and think it’s worth considering.

Ben McPoland has positions in Novo Nordisk. The Motley Fool UK has recommended Novo Nordisk and Tesla. 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

Santa Clara offices of NVIDIA
Investing Articles

£5,000 invested in Nvidia stock 6 months ago is now worth…

Nvidia stock's taking a breather at the moment. But it could be getting ready for its next move higher, says…

Read more »

British coins and bank notes scattered on a surface
Investing Articles

I hold Lloyds. Is it madness to buy Barclays shares too?

Harvey Jones is keen to buy Barclays shares but wonders whether he's simply doubling down, given that he already holds…

Read more »

Asian man looking concerned while studying paperwork at his desk in an office
Investing Articles

It’s time we all took a long, cold look at the Lloyds share price

The Lloyds share price has been good to Harvey Jones, making him a huge fan of the FTSE 100 bank.…

Read more »

Warren Buffett at a Berkshire Hathaway AGM
Investing Articles

Warren Buffett didn’t retire early. But could his investing wisdom help you do so?

Warren Buffett's wisdom from decades of stock market investing is actionable even for a modest investor who simply aims to…

Read more »

Young female hand showing five fingers.
Investing Articles

5 compelling investment ideas for a Stocks and Shares ISA in 2026

Edward Sheldon discusses some ideas to consider for a Stocks and Shares ISA and highlights a UK stock that could…

Read more »

Man writing 'now' having crossed out 'later', 'tomorrow' and 'next week'
Investing Articles

Is this the best time to buy shares in a long time?

Earlier this week, Bill Ackman stated on X that this is the best time to buy shares in a long…

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

£1,000 buys 35 shares in an incredibly reliable FTSE 100 dividend stock

Despite falling 72% from their highs, shares in this FTSE 100 company have been an incredibly reliable source of dividend…

Read more »

Warren Buffett at a Berkshire Hathaway AGM
Investing Articles

This is what Warren Buffett has to say about passive income — and I’m listening!

While searching for new ways to earn passive income, our writer takes to heart sage advice from the Oracle of…

Read more »