How I’d invest £850 a month in a Stocks and Shares ISA to target a million

With a goal and a strategy, our writer outlines his plan to build a £1m Stocks and Shares ISA. Discipline, consistency and quality shares will be needed.

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.

Young female business analyst looking at a graph chart while working from home

Image source: Getty Images

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.

A £1m Stocks and Shares ISA might sound farfetched, but I believe it’s quite achievable. There are some caveats and points to consider. But here’s what I’d do to try to get there.

To begin, I’d set up regular payments into my Stocks and Shares ISA. There are several benefits for doing so. First, it would give me the discipline to invest for a long-term goal.

Reaching £1m won’t happen overnight. In fact, it will probably take many years.

And second, during weaker markets I’d be able to invest at lower prices. This process is known as pound cost averaging and can be really useful in bear markets, much like the one we’re currently experiencing.

Keeping it simple

Picking investments would be my next task. With thousands of potential options, this can be a minefield. But it doesn’t have to be complicated. Often the simplest way to invest is the most effective.

That’s why I’d spend part of my monthly cash on a FTSE 100 or S&P 500 index fund. An exchange traded fund (ETF) is designed to replicate the performance of the underlying index. This low-cost instrument is a hands-off method that requires little additional involvement from me.

The long-term historical return for these funds is around 8%-10%. But let’s say I wanted to aim higher to reach my target a bit earlier.

Boosting returns

To do this, I’d select a few high-quality shares that have long-term growth potential. By this, I mean companies that operate with high margins, growing profits, and what Warren Buffett might call a moat. That’s a sustainable competitive advantage.

I’d also look for high barriers to entry so competitors can’t easily enter my company’s market. As I’m investing for a long period, my chosen shares need to have strong balance sheets and repeatable sales.

Often the shares that meet these criteria have been in business for many years. In my opinion, high-quality companies in the UK include Diageo and RELX. And in the US, they’d include Nike and Apple.

If I ‘d bought these four stocks a decade ago, I’d have made 16% a year.

Sticking to the plan

That said, the stock market doesn’t provide guarantees for future returns. I could lose money as well as make it. But when picking shares to buy, I’d focus on key attributes of the underlying businesses. If a company performs well over time, I reckon there’s a good chance its shares will do too.

I’d note that sometimes there will be periods when my ISA performs poorly. Swings in share prices are to be expected. And during severe bear markets, it’s more important than ever to stick to my plan.

From a combination of quality shares and index funds, let’s say I managed to achieve a long-term return of around 12% a year. By investing £850 a month, I calculate that I would reach my £1m goal in 22 years.

It might sound like the distant future, but those years can fly by.

Harshil Patel has positions in Apple. The Motley Fool UK has recommended Apple, Diageo Plc, and Relx Plc. 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

Three signposts pointing in different directions, with 'Buy' 'Sell' and 'Hold' on
Investing Articles

Could these 3 FTSE 100 shares soar in 2026?

Our writer identifies a trio of FTSE 100 shares he thinks might potentially have more petrol in the tank as…

Read more »

Pakistani multi generation family sitting around a table in a garden in Middlesbourgh, North East of England.
Dividend Shares

How much do you need in a FTSE 250 dividend portfolio to make £14.2k of annual income?

Jon Smith explains three main factors that go into building a strong FTSE 250 dividend portfolio to help income investors…

Read more »

Tesla building with tesla logo and two teslas in front
Investing Articles

275 times earnings! Am I the only person who thinks Tesla’s stock price is over-inflated?

Using conventional measures, James Beard reckons the Tesla stock price is expensive. Here, he considers why so many people appear…

Read more »

Investing Articles

Here’s what I think investors in Nvidia stock can look forward to in 2026

Nvidia stock has delivered solid returns for investors in 2025. But it could head even higher in 2026, driven by…

Read more »

Investing Articles

Here are my top US stocks to consider buying in 2026

The US remains the most popular market for investors looking for stocks to buy. In a crowded market, where does…

Read more »

Investing Articles

£20,000 in excess savings? Here’s how to try and turn that into a second income in 2026

Stephen Wright outlines an opportunity for investors with £20,000 in excess cash to target a £1,450 a year second income…

Read more »

DIVIDEND YIELD text written on a notebook with chart
Investing Articles

Is a 9% yield from one of the UK’s most reliable dividend shares too good to be true?

Taylor Wimpey’s recent dividend record has been outstanding, but investors thinking of buying shares need to take a careful look…

Read more »

Snowing on Jubilee Gardens in London at dusk
Value Shares

Is it time to consider buying this FTSE 250 Christmas turkey?

With its share price falling by more than half since December 2024, James Beard considers the prospects for the worst-performing…

Read more »