What should you do with short-term ISA cash?

Do you have cash in your ISA just waiting for a bargain? You could be damaging your returns.

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.

There’s the age-old question of whether it’s better to hold back some ISA cash for when you spot an unmissable bargain, or stay fully invested. I reckon most private investors would be better with the latter.

Over my investing career, the number of times I’ve thought “Wow, I must buy some of these shares, now” is very close to zero. Many times I’ve spotted something and thought it a compelling bargain, but my long-term success rate at spotting obvious grab-it-now shares runs at probably around 50%, which is no better than random!

At today’s ultra-low ISA interest rates, keeping cash in an ISA means you lose out on the returns you could be getting from shares. If you just bought National Grid shares, you’d earn around 5% per year in dividends, or there’s 6% on offer from BP.

You can still switch

Even if you do keep your ISA fully invested, that doesn’t mean you can’t dip into the odd bargain that comes up from time to time. If your ISA allowance is not fully used yet, you can just keep making monthly contributions to it until you have enough for a new purchase — and that gives you more time to fully investigate your short-term hunch.

My only recent example is Sirius Minerals, which I’d been keen on for some time. I finally bought some this month, at a slightly higher price than when I first started looking — but I see it as less risky now, and the time I waited and pondered was time well spent.

Even if you have no spare ISA capacity, you can still go for those occasional sure-fire bargains if you see them, by selling a portion of one of your other investments. That might sound like a diabolical idea to many, but dealing costs are actually very low these days, and if you do it only rarely it could be a good option.

If you have a big investment in, say, BP and you think some would be better in a hot new growth share, then moving the cash could be the right thing to do — selling when there’s a better opportunity is a key part of successful investing.

What to do with cash?

If you have ISA cash ready for a new investment, but there isn’t an obvious new share you want, what should you do? Especially if you’re keen on watching for any short-term opportunities?

I can only speak for myself, but I’d top up one of my existing holdings. I’d look for one paying solid dividends, and one with a narrow buy/sell spread to minimize any costs associated with switching to something new later — and that would pretty much tie me to FTSE 100 shares.

Of my current holdings, the one I’d top up would probably be Aviva, although I might go for Lloyds Banking Group. Both are paying decent dividends, and I think both are undervalued — though Lloyds is probably the more volatile of the two and the one less suited to a possible short-term switch. Other utilities, like SSE, or maybe even a depressed housebuilder like Taylor Wimpey, are among those I’d consider for a bit of spare ISA cash too.

And if you don’t spot that quick bargain, you’ll probably enjoy better returns from being fully invested.

Alan Oscroft owns shares of Aviva, Lloyds Banking Group, and Sirius Minerals. The Motley Fool UK has recommended BP. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.

More on Investing Articles

Investing Articles

With a P/E of 5.9 is this a once-in-a-decade opportunity to buy dirt-cheap easyJet shares?

Today marks a fresh low for easyJet shares, which are falling on a disappointing set of first-half results. Harvey Jones…

Read more »

Investing Articles

Think the soaring Tesco share price is too good to be true? Read this…

The Tesco share price keeps climbing. It's up again today, following a positive set of results, but Harvey Jones says…

Read more »

Artillery rocket system aimed to the sky and soldiers at sunset.
Investing Articles

BAE Systems shares are up 274% in 46 months. And I reckon there could be more to come

Our writer’s been learning about the state of Britain’s defence forces. And he thinks it could be good news for…

Read more »

Stack of British pound coins falling on list of share prices
Investing Articles

5 years ago, £5,000 bought 218 Greggs shares. How many would it buy now?

Greggs sells around 150m sausage rolls every year. But have those who bought the baker’s shares in April 2021 made…

Read more »

Woman riding her old fashioned bicycle along the Beach Esplanade at Aberdeen, Scotland.
Investing Articles

How big does an ISA need to be when aiming for a £500 monthly second income?

What sort of money would someone need to put into dividend shares if they were serious about targeting a £500…

Read more »

Hydrogen testing at DLR Cologne
Investing Articles

Up 1,119% in 65 months, is there anything left to say about Rolls-Royce shares?

Since the pandemic, Rolls-Royce shares have risen over 1,100%. What’s left to say? In fact, James Beard reckons there’s plenty…

Read more »

UK financial background: share prices and stock graph overlaid on an image of the Union Jack
Investing Articles

Why the UK might be the best place to look for growth stocks

Wise is preparing to move its primary listing to the US. But that's exactly why Stephen Wright is looking closer…

Read more »

Engineer Project Manager Talks With Scientist working on Computer
Investing Articles

Is a Stocks and Shares ISA really worth the effort? Here’s what the numbers say…

Mark Hartley breaks down the financial advantages a Stocks and Shares ISA can offer through its generous tax benefits. But…

Read more »