UK statistics
UK ISA Millionaires 2026: How Many + How They Got There
HMRC ISA statistics showed 5,070 UK adults held ISA portfolios worth £1 million or more at 5 April 2023. Analysis by Rathbones projects this rising to approximately 17,500 by April 2026 - a 245% increase in 3 years driven by the £20,000 annual allowance, 8% projected returns, and the compounding effect of decades of tax-free growth.
Headline numbers
- UK ISA millionaires April 2023
- 5,070
- Projected ISA millionaires April 2026
- 17,500+
- Growth since 2016
- +1,000%
HMRC ISA statistics
Rathbones analysis, 8% returns
7-year compounded increase
The detail
HMRC ISA statistics released in 2024 showed that 5,070 UK adults held ISA portfolios worth £1 million or more as of 5 April 2023 - the most recent year with confirmed data. Analysis by Rathbones extrapolated that figure forwards, projecting the total to rise to over 17,500 ISA millionaires by April 2026 under an 8% annual return assumption with full £20,000 allowance use.
Even under more conservative assumptions, the projection rises substantially. At 5% annual returns with full allowance use, the count rises to approximately 12,300 by April 2026. With no further contributions (just compounding on the existing 5,070-strong base), the count would still rise to around 9,300 - showing how powerful tax-free compounding becomes after the first £600,000-£800,000 of capital is in place.
The total number of ISA millionaires has grown by over 1,000% in the seven years since 2016. The acceleration reflects three forces: the £20,000 annual allowance (frozen at this level since 2017/18 but eroded by inflation), strong stock-market performance 2009-2024, and the fact that the earliest PEP/ISA savers (1987 onwards) are now 35+ years into their compounding journey.
Practical implication: ISAs are now creating more sterling millionaires per year than the National Lottery. Almost all UK ISA millionaires reached that mark via Stocks & Shares ISA (not Cash ISA). The pattern is a long compounding window, full annual allowance use, equity-heavy allocation (FTSE 100 / global trackers / dividend reinvestment), and minimal trading.
Sources
- Rathbones - ISA millionaires set to more than treble over three years (retrieved 2026-06-21)
- HMRC - Individual Savings Account (ISA) statistics (retrieved 2026-06-21)
- Our methodology & full source list →
Related statistics
- Top 1%
Being in the UK's top 1% of income earners requires total pre-tax income of roughly £201,000 per year (HMRC Personal Incomes Statistics, tax year 2022/23 - the most recent complete dataset).
- What Counts as Rich
There's no official "rich" threshold, but HMRC data points commonly used as proxies: top 1% income (~£180k/year), additional rate tax band (>£125,140), or top 10% wealth (>£1m household).
- Pension pot needed
The Pensions and Lifetime Savings Association (PLSA) Retirement Living Standards split single-person retirement income into Minimum (£14,400/yr), Moderate (£31,300/yr), and Comfortable (£43,100/yr) for 2026/27. Using the 4% safe withdrawal rule, the pension pots needed are roughly £469,000 for Moderate and £764,000 for Comfortable - on top of the new State Pension.