Ahead of Isa deadline day, the mood is apprehensive following Donald Trump's unveiling of his tariff plan, which has shrunk the value of many stocks and shares Isas.
The Treasury said reforms will aim to 'get the balance right between cash and equities to earn better returns for savers and boost the culture of retail investment.'
The Chancellor was said to be considering the idea of reducing the amount that can be saved into cash Isas annually to encourage people to direct more money into stocks and shares.
When people talk about Isas, they tend to mean cash or stocks and shares versions. But there is a fifth type almost everyone has forgotten about - the Innovative Finance Isa.
Major firms argue that almost £300 billion sitting in cash Isas would generate better returns - and help Labour's growth mission - if it was instead invested in the much riskier stock market .
Financial companies have told the Chancellor that the £300 billion held by Britons in cash Isas could be yielding better returns for savers if they opted for riskier stocks and shares Isas.