You may have seen recent reports about changes to ISA rules. The Treasury has now confirmed a number of reforms that will affect how cash can be held within ISAs, particularly within Stocks and Shares ISAs and other investment-based ISA arrangements.
While the final legislation is expected to be introduced following a short technical consultation later this year, the direction of travel is now much clearer and investors should begin to consider what these changes may mean for them.
For many years, holding cash within a Stocks and Shares ISA has been a sensible and flexible strategy. It has allowed investors to keep funds within the tax-efficient ISA wrapper while retaining the option to invest at a later date. In many cases, this provided a useful balance between tax efficiency and accessibility.
However, from 6 April 2027, interest paid on cash held within a non-cash ISA will be subject to a flat-rate charge of 22%. The Treasury has confirmed this measure as part of a package of anti-circumvention rules designed to reinforce the distinction between ISAs intended for investment and those intended for cash savings.
The government has also confirmed that portfolios invested entirely in money market funds will be treated as cash for these purposes. While money market funds will remain permissible investments within a Stocks and Shares ISA, they cannot represent 100% of the portfolio if investors wish to avoid being treated as holding cash.
Alongside these changes, the annual Cash ISA subscription limit will be reduced to £12,000, and transfers from non-cash ISAs into Cash ISAs will no longer be permitted. Investors will still be able to transfer from a Cash ISA into a Stocks and Shares ISA or another investment-based ISA.
Importantly, the reforms will apply only to individuals under the age of 65.
What does this mean in practice?
For investors who hold significant cash balances within a Stocks and Shares ISA for extended periods, the new rules may reduce some of the advantages of doing so. Cash that is expected to remain uninvested for the foreseeable future may be more appropriately held within a Cash ISA, subject to the revised subscription limits.
Similarly, investors who have historically used money market funds as a temporary holding position may need to review their arrangements to ensure they remain aligned with the new rules.
There is no need for immediate action. The existing rules remain in place until April 2027, and further detail will be published once the legislation is finalised. However, the changes provide a useful opportunity to review how ISA allowances are being used and whether current arrangements remain appropriate for long-term objectives.
As always, our role is to ensure your assets remain structured in the most suitable, flexible and tax-efficient manner possible. We will continue to monitor developments closely and will contact affected clients should any changes to their arrangements become advisable.
