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How I’d use dividend shares to turn a £20k ISA into a £1k monthly second income

Our writer explains how they’d aim to build a substantial tax-free passive income stream by investing in high-quality dividend shares inside an ISA.

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In my view, dividend income represents a steady and dependable source of passive income. It can help investors build both long-term wealth and financial independence.

What’s more, unlike other passive income streams, such as rental properties or royalties, dividends require minimal effort on my part once I’ve made the initial investment.

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With that in mind, here’s my plan for using dividend shares to turn a £20,000 Stocks and Shares ISA into a £1,000 monthly passive income.

Building a passive income stream

Buying income shares with the aim of generating a substantial secondary income from a £20,000 ISA would take a while. That said, it’s certainly achievable.

But even if I had enough cash available to invest my full ISA allowance in one go, I won’t be anywhere close to my target.

With careful planning and investment selection, however, I could harness the power of compounding and dividend reinvestment. This would be key to helping me build a portfolio that generates £1,000 a month in tax-free dividend income.

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.

Harnessing the magic of compound returns

Historically, Stocks and Shares ISAs have performed well. As my colleague points out, their average annual rate of return over the past 10 years is 9.64%.

This has by no means been a smooth ride though. To illustrate, in 2019/20 the average S&S ISA return was a 13% loss.

Moreover, there’s no guarantee I could achieve a 9% annualised return moving forward. Nevertheless, there are a few high-quality dividend-paying companies that are currently forecast to yield above the 7%-8% mark.

In particular, I’m keeping my eye on Phoenix (9.4% yield), Aviva (7.8% yield), and M&G (10.1% yield).

But while it can be tempting to chase the companies yielding the highest, I always look to identify those with a history of sustainable dividend yields and strong cash flows.

Creating a long-term mindset

One thing for me to keep in mind is that investing in dividend shares involves an element of risk. This includes sharp market fluctuations and the possibility of dividend cuts or suspensions.

Additionally, relying heavily on a few dividend stocks increases the risk of exposure to individual company performance.

That said, with a long-term perspective and a well-executed strategy that employs diversification, I should be well-equipped to ride out the inevitable periods of volatility.

Enjoying a £1k monthly second income

With this in mind, let’s say I manage to achieve an 8% return on a single ISA allowance of £20k. After about 28 years I’d have an investment pot worth around £170,000. And this would be without making any additional contributions in that timeframe!

From here, if I could continue to earn an average yield of 8% from my holdings, I’d receive around £13,600 in annual dividend income. This equates to a £1,133 monthly second income.

In the end, if I can stick to my long-term strategy of focusing on high-quality dividend shares and harnessing the power of compound returns, I’d be well-positioned to reach my goal of £1,000 a month in passive income.

Matthew Dumigan has no position in any of the shares mentioned. The Motley Fool UK has recommended M&g 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.

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