Here’s how compounding is the key to Stocks and Shares ISA growth

Should we take out our Stocks and Shares ISA income each year, or reinvest it in more shares? The difference it makes could be huge.

| 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.

Close-up of British bank notes

Image source: Getty Images

What’s the best kind of ISA to go for, a risky Stocks and Shares ISA or a safe Cash ISA?

I don’t want a Cash ISA because the long-term returns are so poor. But they can be a boon for people who want the guaranteed safety they offer. Not everyone’s happy with stock market risk.

Whatever we go for, what difference would a few percent make anyway? Over just one year, maybe not a lot. But over the long term, it could add up to quite a bit. And it’s all down to the magic of compounding.

Compound returns

Hargreaves Lansdown senior investment analyst Joseph Hill tells us: “We asked people what they’d end up with if they invested £10,000 for a year, and their investments grew at 8%, compounded daily. Just 28% of people got the answer right. The most common answer was £10,800 – which is 8% growth without compounding.

What’s the correct answer? It’s £10,832, and the key is the bit about compounding daily. If the annual 8% is spread out with a tiny proportion paid every day, the first day’s income then earns its own return for the next 364 days. Then the next day’s income compounds for 363 days, and so on.

Now, £32 might not be a huge difference. But let’s try a real world example and see the difference that compounding can make over the long term.

Steady dividend stock

I’m going to pick British American Tobacco (LSE: BATS) as the example. It’s on a forecast dividend yield of 7.8%, and it has a long track record of steady payments. Suppose someone invests the same one-off £10,000, which is half an ISA allowance, into this stock and leaves it there for 10 years.

I’ll assume the share price and the dividend don’t change over the whole period. That’s unlikely, but it’s good enough for comparison purposes.

If they take out their dividend cash and keep it in a sack, they’d end up with an extra £780 per year. That would be a total of £7,800 after 10 years, the same as if it was paid all at the end, like in the Hargreaves Lansdown example. It’s 7.8% multiplied by the 10 years.

Years of compounding

But if, instead of just letting the dividends pile up, they reinvest the cash in more British American shares each year? Well, the pot could more than double to £21,000 from those compounded dividends alone. And £21,000 is a lot nicer than the £7,800 we’d expect if we didn’t reinvest the cash. It’s the difference that compounding can make.

I’ve no idea where the British American dividend or share price might go in the next 10 years. And I’d never put all my money into it. I’d be kept awake at night worrying about what might happen to the tobacco industry in the next decade. Diversification is essential.

But this snapshot example shows why we shouldn’t underestimate the power of compounding. And how the longer it goes on, the greater the difference it can make.

Alan Oscroft has no position in any of the shares mentioned. The Motley Fool UK has recommended British American Tobacco P.l.c. and Hargreaves Lansdown 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

British flag, Big Ben, Houses of Parliament and British flag composition
Investing Articles

Back above 10,000! Is the FTSE 100 index on track again?

The FTSE 100 index has been yo-yoing up and down with the latest news headlines around the oil crisis. Where…

Read more »

Finger clicking a button marked 'Buy' on a keyboard
Investing Articles

Stock market correction: Is there still time to buy UK shares cheap?

Long-term investors can do well to stay calm through stock market corrections, and even crashes, and pick up shares when…

Read more »

Warm summer evening outside waterfront pubs and restaurants at the popular seaside resort town of Weymouth, Dorset.
Investing Articles

2 FTSE 100 blue-chips to consider for a new £20k Stocks and Shares ISA

Ben McPoland highlights a pair of high-quality FTSE 100 stocks that have strong momentum on their side yet are trading…

Read more »

Young Caucasian woman with pink her studying from her laptop screen
Investing Articles

Are depressed Lloyds shares just too tempting to miss now?

Lloyds shares are coming under renewed pressure as conflict in the Middle East threatens the fragile global economic recovery.

Read more »

Female student sitting at the steps and using laptop
Investing Articles

7 FTSE 100 shares that look cheap after the 2026 stock market correction

Falling stock markets often present bargain opportunities. Let's take a look at some of the cheapest FTSE 100 shares at…

Read more »

piggy bank, searching with binoculars
US Stock

Up 59% this year, this S&P 500 stock is smashing the index!

Jon Smith points out a stock from the S&P 500 that's flying right now as part of a transformation plan,…

Read more »

Businessman hand stacking money coins with virtual percentage icons
Investing Articles

Stock market correction: a rare second income opportunity?

Falling share prices are pushing dividend yields higher. That makes it a good time for investors looking for chances to…

Read more »

Finger clicking a button marked 'Buy' on a keyboard
Dividend Shares

I just discovered this REIT with a juicy 9% dividend yield

Jon Smith points out a REIT that just came on his radar due to the high yield, but comes with…

Read more »