Share your opinion and earn yourself a free Motley Fool premium report!

We are looking for Fools to join a 75 minute online independent market research forum on 15th / 16th December.

To find out more and express your interest please click here

£20,000 invested in an ISA could make this much passive income per year…

Our writer takes a look at the passive income potential of a £20k Stocks and Shares ISA portfolio invested in the FTSE 100 index.

| 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.

ISA coins

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.

The Stocks and Shares ISA deadline is looming. This means any unused allowance for the 2024/25 tax year must be deposited before midnight on 5 April, or it will be lost forever.

Of course, then the new £20,000 annual allowance kicks in. How much tax-free passive income could a stock investor generate from that amount? That’s the topic I want to explore here.

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.

Index average

The answer depends on what investments an individual buys. Each one will have its own dividend yield, contributing to the portfolio’s overall yield.

If an investor sticks their 20 grand into the Vanguard FTSE 100 UCITS ETF (LSE: VUKE), the yield would be 3.46% (as of 28 February).

The FTSE 100 has dipped a bit in March, so let’s call that 3.5%. What this means is that £20k invested in this FTSE 100 index fund would be expected to earn about £700 back in dividends.

Is that any good? Not if we’re just talking about income — fixed-rate Cash ISAs are still offering interest rates of 4.4%. This means £20,000 in a Cash ISA could safely yield £880 annually, surpassing the dividend income from the FTSE 100 index fund.

However, the FTSE 100 also has the potential for capital appreciation, whereas a Cash ISA offers safety but no growth potential.

For example, the Vanguard FTSE 100 ETF is up 12% in the past year. So if an investor had invested £20,000 12 months ago, they’d now have roughly £23,100. That’s a solid return. 

Global trade headaches

However, there’s no guarantee the blue-chip Footsie will do as well this year. It’s a truly global index, meaning many companies within it face the prospect of navigating a trade war. This could negatively impact earnings and send the FTSE 100 lower from its current level.

Take Diageo, which owns spirits brands like Johnnie Walker, Gordon’s, and Tanqueray. It would feel the impact of US tariffs on tequila imported from Mexico and whisky from Canada. Its brands in these categories — Don Julio, Casamigos, and Crown Royal — are among its most popular with American consumers. So this situation is far from ideal for the drinks giant.

Longer term though, I’m optimistic the FTSE 100 can keep steadily chugging higher. Large constituents like AstraZeneca, HSBC, Rolls-Royce, and data analytics firm RELX have very strong competitive positions and attractive long-term growth opportunities.

But this year’s trajectory is very unpredictable, meaning there is more to consider than just passive income when buying the index.

Aiming for a higher yield

Alternatively, an investor could decide to deploy their £20k into a portfolio of individual UK stocks that yield much higher than the average.

Admittedly, this adds risk because companies have individual challenges and they’re not assured to pay out dividends. But income investors are blessed because there are so many options across the UK market.

Investment firm M&G, for example, is sporting a mighty 9.6% yield for 2025, while insurer Legal & General is offering a 9% payout. If an investor puts £10k into each stock, they could expect £1,860 in passive income.

Of course, owning just two dividend stocks is not advisable. But given the smorgasbord of options available, I think it’s possible to build a diversified £20k Stocks and Shares ISA that yields 6.5%. That would generate £1,300 a year in passive income.

Ben McPoland has positions in AstraZeneca Plc, HSBC Holdings, Legal & General Group Plc, and Rolls-Royce Plc. The Motley Fool UK has recommended AstraZeneca Plc, Diageo Plc, HSBC Holdings, M&g Plc, RELX, and Rolls-Royce 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 For Beginners

Light trails from traffic moving down The Mound in central Edinburgh, Scotland during December
Investing Articles

Start investing this month for £5 a day? Here’s how!

Is a fiver a day enough to start investing in the stock market? Yes it is -- and our writer…

Read more »

Young mixed-race couple sat on the beach looking out over the sea
Investing Articles

Investing in high-yield dividend stocks isn’t the only way to compound returns in an ISA or SIPP and build wealth

Generous payouts from dividend stocks can be appealing. But another strategy can offer higher returns over the long run, says…

Read more »

Two female adult friends walking through the city streets at Christmas. They are talking and smiling as they do some Christmas shopping.
Investing Articles

Here’s how you can invest £5,000 in UK stocks to start earning a second income in 2026

Zaven Boyrazian looks at some of the top-performing UK stocks in 2025, and shares which dividend-paying sector he thinks could…

Read more »

Middle aged businesswoman using laptop while working from home
Investing Articles

3 no-brainer UK shares to buy now for 2026, according to experts

City analysts rate these FTSE 100 and FTSE 250 as great Buys for the New Year. Royston Wild isn't convinced…

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

How much do you need in an ISA to target a £3,000 monthly passive income?

Buying dividend shares can be a powerful way to target an ISA income in retirement. Consider this strategy for a…

Read more »

Front view of a young couple walking down terraced Street in Whitley Bay in the north-east of England they are heading into the town centre and deciding which shops to go to they are also holding hands and carrying bags over their shoulders.
Investing Articles

How much do you need to invest in UK stocks to effectively double your State Pension?

Harvey Jones crunches the numbers to show how much investors would need in a portfolio of UK stocks to get…

Read more »

Night Takeoff Of The American Space Shuttle
Investing Articles

Will the Lloyds share price double in 2026?

The Lloyds share price has been one of the FTSE 100's biggest success stories this year. Royston Wild asks if…

Read more »

Aviva logo on glass meeting room door
Investing Articles

Prediction: in 2026, the Aviva share price could climb to…

Thinking about investing in Aviva? Zaven Boyrazian explores the latest forecasts from expert analysts to see if there's still a…

Read more »