Turning a £20k ISA into a £16,000 annual second income? It’s possible!

By making the most of a £20k ISA using basic investing principles, our writer thinks he could build up to a second income of £16,000 a year.

| 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.

Front view photo of a woman using digital tablet in London

Image source: Getty Images

I own shares in Legal & General (LSE: LGEN) as part of my second income strategy. The company ticks several key principal boxes I’ve outlined below. It’s a solid and reliable dividend payer with a 9% yield — considerably higher than the FTSE 100’s average of 3.5%.

However, the shares have disappointed me of late. Since early 2022, they’ve steadily declined from 307p to 231p. Possibly, high interest rates and stifling inflation bloated expenses and suppressed revenue. Naturally, this would limit capital available to the company for growth and reinvestment.

Yet through it all it’s remained loyal to its shareholders, consistently increasing dividends since 2009. When aiming for passive income, that type of consistency is precisely what I look for. Of course, if the dwindling profits force the insurance giant to cut its dividends, I’ll reassess my position. 

But for now, it’s one of my best earners.

Screenshot from dividendsdata.co.uk

Now, a 9% yield’s at the high end of the scale. On average, I think a good portfolio could achieve a 7% yield and 5% annual price growth. With that, a monthly investment of £300 could grow to around £265,000 in two decades, paying an annual dividend of £16,740.

So how’s this type of portfolio constructed? Here’s my strategy.

Laying the groundwork 

To get the best tax savings, UK residents can invest up to $20k a year via a Stocks and Shares ISA. I believe strategic investing could turn this allowance into a significant second income over time.

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.

To aim for a consistent second income of £16,000 a year, I’ve considered some strategic investment ideas that leverage the full potential of my £20k ISA allowance. This plan involves a combination of regular contributions and smart portfolio management to achieve a sustainable passive income stream.

But bringing in an extra £16k a year isn’t easy. Here are the key investment principles I’d use.

Diversification 

I should just invest in stocks with the highest returns, right? Seems logical. However, these often come with the highest risk. A 30% gain one year could be a 40% loss the next. That’s why it’s best to spread an investment across various asset classes like stocks, bonds and ETFs. Some may have slower growth but can protect an investment when the economy inevitably dips.

Long-term focus

There’s no shortcut to a lucrative second income. It’s best to focus on long-term growth rather than short-term gains. This allows the investment to compound more over time.

Regular contributions

Making small contributions every month can maximise the ISA’s growth potential. This also defends against suffering a big loss by investing a large amount just before a market slump.

Reinvest dividends

As mentioned above, I’d add some stocks that pay dividends as they provide small amounts of regular income. By reinvesting the dividends, the returns will compound even quicker.

Consider index funds

These funds typically include a range of assets, offering an easy way to invest in a diversified portfolio. Some even track the performance of an entire index like the FTSE 100 or S&P 500.

Rebalancing

Markets change constantly due to economic, social and geopolitical events. Periodically reviewing and adjusting the assets in a portfolio can help to reduce risk and maximise returns.

Mark Hartley has positions in Legal & General Group Plc. 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

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

£7,500 invested in BAE Systems shares 10 days ago is now worth…

Why have BAE Systems shares experienced a sudden double-digit pullback? And does this present a buying opportunity for my portfolio?

Read more »

Picture of an easyJet plane taking off.
Investing Articles

£10,000 invested in easyJet shares 4 weeks ago is now worth…

It's been a crazy month for easyJet shares. Here's what would have happened to an investor's £10,000 stake put to…

Read more »

CEO Mark Zuckerberg at F8 2019 event
Investing Articles

Down 31%, is this a rare chance to buy Meta stock for my ISA cheaply?

After rising to near $800 in 2025, Meta stock has pulled back to around $550. Edward Sheldon looks at whether…

Read more »

Santa Clara offices of NVIDIA
Investing Articles

18% off its peak, is Nvidia stock now attractively priced?

Nvidia stock has given up almost a fifth of the price it commanded at its peak over the past year.…

Read more »

Aston Martin DBX - rear pic of trunk
Investing Articles

The Aston Martin share price destruction helps illustrate 5 common investing mistakes!

The Aston Martin share price has been a disaster for investors. Christopher Ruane highlights a handful of lessons we can…

Read more »

DIVIDEND YIELD text written on a notebook with chart
Dividend Shares

How this stock market correction can help boost a second income by 25%

Jon Smith explains how rising dividend yields across some existing income shares can be seen as an opportunity to grow…

Read more »

Middle-aged Caucasian woman deep in thought while looking out of the window
Investing Articles

Considering a SIPP? Today’s market could provide an excellent opportunity to start

Mark Hartley breaks down the benefits of using a SIPP for retirement, and how current market conditions could offer a…

Read more »

Calendar showing the date of 5th April on desk in a house
Investing Articles

Looking for last-minute ISA ideas? Check out these UK stocks before April 3

Easter bank holidays mean the deadline to put cash into a Stocks and Shares ISA might be closer than UK…

Read more »