There are now 2,001 ISA millionaires in the UK with average pots of £1.4m.

The latest data from HMRC reveals an “astonishing” 40% of high earners failed to take out an ISA in the 2018/19 tax year.

Over £79m more was invested into ISAs in April than was invested in total over the previous 12 months.

Clients aged 30-54 are the most likely to have been the first to invest in equity ISAs in the new tax year, according to Hargreaves Lansdown data.