How I’d invest £100 a month in a Stocks and Shares ISA in 2020

Rupert Hargreaves explains why every longer-term investor should open a Stocks and Shares ISA in 2020.

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.

A Stocks and Shares ISA is a great way to save for the future. Even if you can’t afford a big lump sum every month, these tax-free wrappers could help you build a substantial financial nest egg.

Stocks and Shares ISA benefits

Anyone can open a Stocks and Shares ISA and start contributing. Most online stock brokers offer investment plans starting from as little as £50 a month. You can put up to £20,000 a year away too.

Any income or capital gains earned on the cash stashed inside one of these wrappers doesn’t attract tax liabilities. You don’t even need to declare the ISA on your tax return. That makes the product especially attractive for higher rate taxpayers.

The tax-efficient nature of a Stocks and Shares ISA means it’s also an excellent instrument for savers. As the £20,000 is a use-it-or-lose-it allowance, it makes sense to use as much as possible every year. There’s no penalty for withdrawing your money, so you can always take it out at a later date.

Even a relatively modest investment of £100 a month can add up to big bucks in a Stocks and Shares ISA.

Investing for the future

Choosing the investments for this ISA can be a challenging process. However, the best strategy could be to use low-cost index funds. Investors who are saving for the next three-to-four decades would benefit from investing in a low-cost FTSE 250 or FTSE 100 tracker fund.

Meanwhile, investors saving for the next one-to-two years might benefit from buying a low-cost equity income tracker fund.

Investors with a shorter time horizon than five years might be better off buying bond funds, or staying in cash. It’s impossible to tell where the market will go in this short time frame.

A contribution of £100 a month could yield substantial results over the long run. The FTSE 250 has produced an average annual return of 12% since its inception three-and-a-half-decades ago. Based on these figures, an investment of £100 a month in the index over this time frame would be worth £650,000 today.

Long-term profits

There’s no guarantee the FTSE 250 will produce similar returns in the near term. Still, over the next few decades, it’s highly likely the index will match its long-run average.

Assuming the global economy is bigger in 10 years than it is today, the index constituents should also be more substantial. Efficiency improvements and dividend distributions will help improve profits and shareholder returns. That should translate into more significant profits for investors.

As such, if you have a spare £100 a month to invest, and an investment horizon of three-to-four decades, opening a Stocks and Shares ISA and setting up a monthly investment plan in the FTSE 250 may be the best way to grow your hard-earned money over the long run.

Rupert Hargreaves 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

A pastel colored growing graph with rising rocket.
Investing Articles

Here’s how I’m targeting £12,959 a year in my retirement from £20,000 in this ultra-high yielding FTSE 100 income share…

Analysts forecast this high-yield FTSE 100 income share will deliver rising dividends and capital gains, making it a powerful long-term…

Read more »

A senior man using hiking poles, on a hike on a coastal path along the coastline of Cornwall. He is looking away from the camera at the view.
Investing Articles

Is Diageo quietly turning into a top dividend share like British American Tobacco?

Smoking may be dying out but British American Tobacco remains a top dividend share. Harvey Jones wonders if ailing spirits…

Read more »

Young woman holding up three fingers
Investing Articles

Just released: our 3 top income-focused stocks to consider buying in December [PREMIUM PICKS]

Our goal here is to highlight some of our past recommendations that we think are of particular interest today, due…

Read more »

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

Tesco’s share price: is boring brilliant?

Tesco delivers steady profits, dividends, and market share gains. So is its share price undervaluing the resilience of Britain’s biggest…

Read more »

Businessman hand stacking money coins with virtual percentage icons
Investing Articles

1 huge takeaway from the Martin Lewis investing presentation

Martin Lewis showed how returns from stocks have smashed the returns from cash savings over the last decade. But here’s…

Read more »

Middle aged businesswoman using laptop while working from home
Investing For Beginners

I think the best days for Lloyds’ share price are over. Here’s why

Jon Smith explains why Lloyds' share price could come under increasing pressure over the coming year, with factors including a…

Read more »

A graph made of neon tubes in a room
Investing Articles

£5,000 invested in the FTSE 100 at the start of 2025 is now worth…

Looking to invest in the FTSE 100? Royston Wild believes buying individual shares could be the best way to target…

Read more »

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

Can the BAE share price do it again in 2026?

The BAE share price has been in good form in 2025. But Paul Summers says a high valuation might be…

Read more »