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To earn a stable £1,667 monthly income from the stock market you would need roughly £500,000 invested. This is based on the recommended 4% withdrawal rule, eyeing a potential 30-year-long retirement.
Half-a-million’s a big number. But with steady saving, ISA tax benefits, and the miracle of compounding returns, it’s not as crazy as it sounds. With a Stocks and Shares ISA, UK investors pay no tax on capital gains or dividends. That makes a big difference over 10-20 years.
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.
Turning regular savings into £500k
Imagine you start by using this year’s Stocks and Shares ISA limit to invest £20,000, then keep adding £500 every month in the years after that opening year. The key is to invest in solid dividend stocks and reinvest all the returns for years.
Let’s say the portfolio returns around 10% a year on average (price growth plus dividends). A rough sum, say £20,000 up front plus £6,000 a year in contributions, can grow to about £500,000 in around 20 years — if markets play ball. That is because the pot is not just growing from your £500 a month, but also from growth on all the money already invested.
In the early years it feels slow, but after a decade, the growth accelerates.
An appropriate example
Compass Group (LSE: CPG) runs catering and support services for organisations all over the world. It has long, sticky contracts and serves millions of meals a day, making revenue fairly steady.
Over the last 20 years, its share price has risen about 430%, which works out at roughly 9% a year in price growth. On top of that, its dividend yields typically around 1%-2% a year, taking the total return to above 10%. That kind of compounding is exactly the sort of pattern a long‑term ISA investor is trying to copy.
Recent results back up the ‘steady compounder’ story. In its 2024 full‑year numbers, it reported revenue of about $42bn, up around 11% on the year, and lifted its operating margin to roughly 7.1%. Earnings per share (EPS) and free cash flow both grew strongly, and return on capital employed (ROCE) sits in the high teens to mid‑20s – impressive for a large, mature business.
Pros, cons and risks
Compass looks attractive because it operates in everyday areas such as workplace and stadium catering. With demand fairly steady, it has delivered strong growth and cash generation over many years, paying a growing dividend with a yield of around 2%. This is supported by a sensible payout ratio of roughly 60%, leaving room to reinvest and expand.
Still, that yield is meagre compared with more popular UK income shares.
On the risk side, rising wages and food inflation could squeeze margins if Compass cannot fully pass on costs. Given it often trades on a premium to the wider FTSE, investors are already paying an inflated price. Yes, it’s a high‑quality company, but it must keep delivering or risk a correction.
The bottom line
For a British saver considering an ISA for retirement, a stock like Compass is a core long‑term holding to consider. It’s not a get‑rich‑quick play, rather a business with the kind of steady, compounding profile that makes reaching a £500,000 portfolio over a couple of decades a realistic goal.
