Did you know that across the UK today, there are thousands of ISA millionaires? These individuals – who predominantly invest with Hargreaves Lansdown, AJ Bell, and Interactive Investor – have been able to build up ISA portfolios worth seven figures. Wondering how they did it? Here’s the secret to becoming an ISA millionaire.
ISA millionaire strategies
While there are many different ways to build up a million-pound ISA, ISA millionaires tend to have a few things in common. First, they’ve taken advantage of ISA allowances. By regularly contributing to their ISA accounts, they have been able to build up large amounts of capital. Note that today, the annual allowance is £20,000 – that’s a very generous allowance and it could help you build significant wealth given that gains and income within an ISA are tax-free.
Second, they’ve invested their money. Research from Interactive Investor shows that even if you had maxed out your ISA allowance every year since 1987 when personal equity plans (PEPs) were introduced (these preceded ISAs), you’d only have about £435,000 today. So, ISA millionaires have clearly invested their money for growth. We’ll cover what they typically invest in shortly.
Third, they’ve been disciplined and patient. Building a million pound ISA takes time. Realistically, it’s not going to happen overnight. That said, Hargreaves Lansdown recently revealed that its youngest ISA millionaire was only 27, so it is possible to get there quickly with the right investments.
Hargreaves Lansdown’s ISA millionaire tips
It’s worth noting that in 2025, Hargreaves Lansdown provided some insight into how its ISA millionaires invest. It said that its customers tend to:
- Use their ISA allowances early – by contributing to an ISA early on in the tax year you can potentially invest for longer.
- Ignore short term noise and don’t trade a lot – many of its ISA millionaires have gotten rich over time by allowing their investment returns to compound over decades.
- Have diversified portfolios – diversification can help to reduce risk and give you a better chance of investment success.
In other words, they contribute to their ISAs regularly, invest in a broad range of assets, and then focus on the long term.
AJ Bell’s ISA millionaire investments
More recently, AJ Bell provided some insight into the investments that are popular among its ISA millionaires. At the end of 2025, the most popular shares among these investors were:
- Shell
- GSK
- Legal & General
- National Grid
- Aviva
- BP
- Lloyds
- Haleon
- HSBC
- AstraZeneca
Looking at these stocks, there’s a clear preference for blue-chip dividend stocks. Note, however, that these stocks might not be the best choices for someone starting their ISA millionaire pursuit today.
As for funds, the most popular products among AJ Bell’s ISA millionaires were:
- iShares Core FTSE 100 ETF
- iShares Physical Gold ETF
- Vanguard S&P 500 ETF
- Vanguard FTSE Developed Asia Pacific ex-Japan
- Vanguard FTSE 100 ETF
- Vanguard FTSE Japan
- ETFS Physical Silver
- Vanguard FTSE 250 ETF
- Artemis Global Income
- WisdomTree Physical Gold
This list suggests that they diversify across several different asset classes including UK equities, US equities, Asian equities, gold, and silver.
How long does it take to become an ISA millionaire?
While becoming an ISA millionaire is a very achievable goal, it’s likely to take time. The exact time will depend how much you contribute to your ISA every year and the returns you’re able to generate. As an example, if you were to contribute £20,000 per year and you achieved a return of 8% after fees, you’d get there in about 20 years. If you were to contribute £10,000 per year and you achieved a return of 8%, you’d get there in about 28 years.
In summary, to become an ISA millionaire you’ll have to contribute to your ISA regularly, and take on some risk by investing your money. You’ll then have to be patient and stick to your long-term plan. The more money you have invested over the longest possible period, the bigger the chance you have of achieving ISA millionaire status. Ultimately, the goal is to enable compounding to work its magic.
Based in London, Edward is a distinguished investment writer with an extensive client portfolio comprising a diverse array of prominent financial services firms across the globe. With over 15 years of hands-on experience in private wealth management and institutional asset management, both in the UK and Australia, he possesses a profound understanding of the finance industry.
Before establishing himself as a writer, Edward earned a Commerce degree from the prestigious University of Melbourne. Complementing his academic background, he holds the esteemed Investment Management Certificate (IMC) and is a proud holder of the Chartered Financial Analyst (CFA) qualification.
Widely recognised as a sought-after investment expert, Edward’s insightful perspectives and analyses have been featured on sites such as BlackRock, Credit Suisse, WisdomTree, Motley Fool, eToro, and CMC Markets, among others.
