Almost 5,000 people had racked up more than £1 million in individual savings accounts (ISAs) by 2022, HM Revenue and Customs figures show.
Some 4,850 people had in excess of the figure come the end of the 2022 financial year, against 4,070 in 2021.
Average savings among these ‘ISA millionaires’ sat at £1,351,000, according to the figures, while pots among the top 25 investors sat at £8,880,000.
The figures were obtained through a freedom of information request by money app Plum, though HMRC cautioned these reflected more of a guide given potentially incorrect data from account managers.
Plum public relations head Rajan Lakhani noted “ISA millionaire wealth” had continued to grow, even as other products lost “a little of their shine following recent tax changes”.
“A large part of the ISA’s appeal is the flexibility and liquidity it offers investors,” he said.
“While only a fraction of savers will be able to amass a million pounds in their Isa, investing even small amounts regularly can add up to a significant sum over time.”