ISA investors are expected to save £6.7 billion in tax this year – up a third compared to the previous tax year and more than doubling over the past five years.
The tax-free savings and investment wrappers saved £4.9 billion in the tax year that finished this April, according to the Office for National Statistics. Five years ago the total tax saving was £3.5 billion.
Higher interest rates and extra capital gains tax and dividend tax savings have led to the expected rise in the current period.
Capital gains tax, which kicks in when you make a gain above the annual allowance, with the allowance cut from £12,300 to £6,000 in the current tax year, pushing more investors over the limit.
Last April the allowance before paying tax on dividends also fell from £2,000 to £1,000.
Earlier this week ONS data also showed the shifting ownership of UK investors in the equity market, with the proportion of shares held by UK investors shrinking to 31.5% at the end of 2022 from around 34% in 2020.
Of this, individual investors held 10.8%, down by 1.2 percentage points from 2020.