Want to give up work and live off passive income? I’ve been thinking about it more and more. That’s why I’m trying to understand how big an ISA would need to be to generate a full income purely from dividends, using real UK earnings data as a benchmark.
But life is expensive. No matter what age you are, there are all sorts of living costs that need to be met. The ONS says average UK earnings are around £742 a week — roughly £38,584 a year. So with that in mind, how much would you actually need in a Stocks and Shares ISA to replace that income entirely? Let’s see.
Crunching the numbers
To generate £38,584 a year in passive income, an investor would need a portfolio of around:
- £771,680 at a 5% yield
- £643,067 at a 6% yield
- £551,200 at a 7% yield
However, there is an important difference that needs to be factored in.
The £38,584 figure is a gross salary, which would typically be subject to income tax and National Insurance in the real world. By contrast, income generated inside a Stocks and Shares ISA is tax-free. That means the equivalent after-tax income required from dividends would be lower than the headline salary figure suggests.
Still, even with that advantage, these figures show how demanding a pure income-only approach can be.
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Beyond headline yields
That’s the theory — but in practice, I think there is another way to think about this problem.
Rather than focusing purely on the yield required today, I prefer to look at businesses that can grow their income over time. The idea is that even a starting yield that looks modest today can become far more powerful if the underlying dividend grows consistently over a number of years.
This shifts the focus away from trying to ‘buy’ a fully formed income stream upfront, and towards building one gradually through reinvestment and earnings growth.
Companies that increase dividends regularly tend to be those with improving earnings, strong balance sheets, and sustainable competitive positions. Over time, that combination can matter more than starting yield alone.
Global bank income engine
If reinvesting dividends is the engine of long-term income, the next question is which businesses can realistically sustain and grow those payouts over time.
One name I believe fits that profile is HSBC (LSE: HSBA).
A large portion of the bank’s profits now comes from Asia, particularly through wealth management and long-term savings flows. That matters because it ties the dividend more to structural growth in Asian investment activity than to short-term economic cycles in any single market.
Recent performance supports that trend. Earnings have beaten expectations, returns have strengthened, and dividends have continued to rise alongside ongoing share buybacks. The stock currently yields 4.2%, but more importantly, that payout has been moving in the right direction.
What stands out is the ability to generate consistent surplus capital from its Asian franchise, where deposit growth and wealth accumulation continue to underpin earnings power.
Of course, risks remain, particularly if global growth slows or credit conditions tighten.
But for investors trying to bridge the gap between today’s income and a long-term ISA target, HSBC offers a rare combination of scale, stability, and exposure to one of the world’s most structurally important growth regions.
