Interactive Investor

Where do ISA millionaires invest?

6th February 2023 09:48

by Jemma Jackson from interactive investor

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Tough year sees millionaire numbers dip, but investment trusts continue to power portfolios.

ISA millionaires 600
  • 852 ISA millionaires on ii platform – down from 983 in 2022
  • Millionaire ii ISA holders have almost twice as much investment trust exposure 
  • ISA millionaires make four times the number of trades in a year than typical ii ISA customer
  • ISA millionaires hold 50% less cash than the typical ISA customer

A total of 852 ISA millionaires are with interactive investor, the UK’s second-largest investment platform for private investors, which today publishes its annual ISA millionaire’s data.

The total (as at 31 January 2023) is down from the 983 recorded at the same time last year, with tough market conditions affecting valuations, but still significantly above the 731 recorded at the beginning of 2021.

Crucially, instead of charging a percentage fee on customer wealth, interactive investor charges a flat monthly fee of £9.99 per month for its core Investor price plan. That means customers get to keep more of their own money, and the savings can be substantial and life-changing over a lifetime of saving. 

The average age of an interactive investor ISA millionaire is 73, compared to an average age of 56 for the overall ISA cohort. Most will likely have started out with Personal Equity Plans (PEPs), when ISAs were just a twinkle in policymakers’ eyes. So, the number one lesson is patience – ISA millionaires didn’t get there overnight.

Where are ISA millionaires putting their money?

Investment trusts are continuing to power ii ISA millionaire portfolios and account for the largest share of ISA portfolios (42.5% compared to just 8.2% for funds). 

For ii’s broader ISA base, investment trusts and funds tend to have similar prominence in portfolios (24% investment trusts, 22% funds).

Investment trusts are ahead of direct equities (39.9%) in terms of asset split and Exchange-Traded Products (3.7%). ISA millionaires are also holding close to 50% less in cash (5% versus 10% cash for the broader ISA base), suggesting that ISA millionaires are studiously avoiding the long-term effects of cash drag.

Asset splits
















Investment Trusts






Dzmitry Lipski, Head of Funds Research at interactive investor, says: says: “Congratulations to all the fortunate customers who have been able to grow their ISA pots to £1 million-plus. With an average age of 73 compared to 56 for our overall ISA cohort, this is very much about getting rich slowly. 

“Most of our ISA millionaires will have likely started life in PEPs, which preceded ISAs, a reminder that long-term wealth creation is about discipline and process. That means utilising government tax wrappers, a great rule of thumb, even if millionaire status might prove elusive for most of us. 

“It’s no surprise to see investment trusts take up such a large proportion of customer portfolios. Over the long term, some unique features such as gearing (borrowing) to enhance returns have helped them deliver strong long-term returns overall. Over time that might mean that they might start to account for a larger percentage of a portfolio. Some investors might consider rebalancing, particularly if a very adventurous investment trust is suddenly taking up a big share of the pie due to outperformance.

“Remember also that that those same investment trust bells and whistles mean they can also underperform in a falling market, and because they are listed on the stock market, trusts can also be impacted by sentiment. But the data shows that investment trusts should not be overlooked. 

“FTSE blue-chips are widely held in ISA millionaire accounts, and while these tend to have strong overseas earnings, the ultimate overseas exposure has been sought via global investment trusts, with Alliance Trust (LSE:ATST) the most held overall stock among ISA millionaires, and Scottish Mortgage (LSE:SMT) in third place.

“Finally, ISA millionaires only have an average of 5% cash in their portfolios compared to 10% across all ISA accounts, so they are putting more of their money to work. Long term, this can help avoid cash drag. While it’s inspiring to look at how the very wealthiest have got there, it’s also important to consider your risk profile and individual circumstances.”

When do ISA millionaires invest?

It seems that ii ISA millionaires are almost as likely to be tax-year early birds as they are to join the last-minute ISA rush. Some 45% of total 12-month subscriptions from ii ISA millionaires were added between 6 and 30 April 2022. When we look across all ii ISAs, 27% of the total 12-month subscriptions were deposited between 6 and 30 April 2022. Those long-term early bird investors will have an additional year in the market, which will also help power portfolios in a rising market.

Myron Jobson, Senior Personal Finance Analyst, interactive investor, says: “The early bird gets the bigger worm it seems when it comes to ISA investments – that’s because more of your assets are working for you for longer. There will be inevitable market timing risk, and that’s why a long-term view is crucial. But it seems to be working for ISA millionaires.

“But whether early bird or last minute, the main thing is to take advantage of the ISA wrapper, regardless of whether you are able to use the full amount – and £20,000 a year takes some investing. Another good option is to drip-feed your investments on a monthly basis to help smooth out some of the inevitable bumps in the market, and you can do this from £25 per month.”

ISA millionaires made more than four times the number of trades on average (25.4), than were recorded across all ISA accounts on ii (5.8), and this may well be for rebalancing purposes.

ISA millionaire’s top picks

As they did last year, investment trusts feature strongly among ii ISA millionaire’s top 10 holdings, with Alliance Trust the most held and Scottish Mortgage Trust in third place, sandwiching Shell (LSE:SHEL), the second most-popular holding.

Popular big FTSE 100 blue-chip names continue to appeal to ii investors.

Top 10 most-held instruments – ranked by number of customer holdings

Geographical breakdown

Within direct equity allocation, there continues to be a clear home bias. ISA millionaires have 91.3% exposure to the UK (up from 88% last year) – a trend across broader ii ISA savers, which have an average of 86.9% UK exposure. This may well be due to the outperformance of the FTSE 100 last year compared to global indices. ISA millionaires have a little less in the US versus ii’s wider customer ISA base (8% versus 11.3%).

How long will it take to become an ISA millionaire?

The amount of time it takes to become an ISA millionaire will vary, and ultimately this will depend on the amount you can invest, as well as your investment return.

Were you to start now and invest the full £20,000 annual ISA allowance (assuming it stays the same), and your investment saw 5% annual growth (not easy, and definitely not guaranteed) excluding fees, it would take 25 years to reach the £1 million mark - £1,002,269.08, to be exact.

If your investments grew by 7% net of fees (an even taller order), you could trim three years off that period, achieving £1,048,722.82 in 22 years. 

If your investment experienced annual growth of 3%, it would take 31 years to reach the seven-figure sum (£1,030,055.17).

Gender breakdown

Some 66% of ii’s ISA millionaires are male, and 34% female, broadly in line with ii’s wider ISA customer base (65% male and 35% female). 

Female ISA millionaires have more in investment trusts then men (44.1% versus 40.7%), and less in direct equities (36.6% versus 42.8% for men).

When picking individual stocks, women have more UK exposure (94.4% versus 90.3% for men). 


Looking at regions, the three regions with the highest proportion of ISA millionaires are in South East England (24.4%), London (22.2%) and Scotland (11.7%).

These articles are provided for information purposes only.  Occasionally, an opinion about whether to buy or sell a specific investment may be provided by third parties.  The content is not intended to be a personal recommendation to buy or sell any financial instrument or product, or to adopt any investment strategy as it is not provided based on an assessment of your investing knowledge and experience, your financial situation or your investment objectives. The value of your investments, and the income derived from them, may go down as well as up. You may not get back all the money that you invest. The investments referred to in this article may not be suitable for all investors, and if in doubt, an investor should seek advice from a qualified investment adviser.

Full performance can be found on the company or index summary page on the interactive investor website. Simply click on the company's or index name highlighted in the article.

Please remember, investment value can go up or down and you could get back less than you invest. If you’re in any doubt about the suitability of a stocks & shares ISA, you should seek independent financial advice. The tax treatment of this product depends on your individual circumstances and may change in future. If you are uncertain about the tax treatment of the product you should contact HMRC or seek independent tax advice.

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