Cash ISA balances surged to a total £359.2bn in the third quarter, new analysis from Paragon Bank has highlighted.

The group’s analysis of CACI data showed that Q3 saw savers add a further £7.6bn to their cash ISAs.

Since the start of the year, the growth of ISA balances has outpaced non-ISA variants. Savers have grown adult cash ISA balances by £37.7bn, or 11.7%, since the end of January.

Over 2024, non-ISA savings account balances have recorded slower growth, increasing by £3bn, or 0.4%.

Furthermore, Paragon’s findings indicated that ISA savers have favoured fixed rate variants. Since the start of the year, fixed rate adult cash ISA balances have grown by £26.4bn, representing 70% of the overall growth in 2024. During Q3, fixed rate ISA balances also grew from £188.5bn to £194bn, with instant access variants increasing from £156.4bn to £158.7bn.

“With £7.6bn added just in the last quarter and an overall increase of £37.7bn since January, it's clear that the benefits of tax-free savings are resonating strongly with savers,” said Paragon managing director of savings, Derek Sprawling. “Notably, fixed rate ISAs have seen substantial interest, accounting for 70% of the growth in 2024.”

He added: “This tax year is drawing to a close in April and we would urge savers who intend to utilise their ISA allowance to act early to beat the rush.”

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