New ISA Rules to Take Effect from April 2027
Millions of savers could see a major shake-up to their tax-free savings under Rachel Reeves' planned reforms to Individual Savings Accounts (ISAs), with new rules due to take effect from April 2027. Under the changes, savers will be charged a flat 22% tax on any interest earned on cash held within Stocks and Shares ISAs.
The move has been designed to encourage people to actively invest in the stock market to boost the country’s economy, while stopping savers from using Stocks and Shares ISAs as a workaround to hold cash tax-free. The changes follow an earlier announcement that the annual Cash ISA allowance will be reduced from £20,000 to £12,000 for those under 65.
The new rules announced last week (June 23) have raised concerns among investors who rely on ISAs as a simple and predictable way to grow their savings without tax complications. Experts at BrokerChooser say there are three key points investors should be aware of before the rules come into force.
Slashing Cash Limit
While the overall annual ISA allowance will remain at £20,000, anyone wishing to max out their full limit will be forced to place the remaining £8,000 into investments, such as a Stocks and Shares ISA. However, any portion of that £8,000 left as uninvested cash will immediately trigger the new 22% tax on interest, regardless of the saver's age.
Further rigid restrictions will lock down movement between accounts. Under-65s will be completely banned from transferring funds out of Stocks and Shares ISAs into Cash ISAs, though transfers in the opposite direction will still be allowed. This restriction will only be lifted once a saver celebrates their 65th birthday.
Rethinking Investments
One option still available is holding cash-like investments such as Money Market Funds within a Stocks and Shares ISA. Returns from these can remain entirely tax-free, provided they do not make up 100% of the portfolio. As there is no fixed minimum requirement for other investments, savers could technically keep tax efficiency by holding even a very small amount in shares alongside cash. In practice, this means investing as little as 1p in the stock market could allow the rest of their Money Market Fund returns to remain tax-free.
However, the reforms could make holding large amounts of cash inside investment ISAs far less attractive, potentially pushing savers towards higher-risk options. Savers may face a choice between accepting tax charges, moving funds elsewhere or increasing their exposure to investment risk.
Concerns Over Complexity
While the Government hopes the changes will encourage more long-term investment and support economic growth, there are concerns that added complexity could deter some from using ISAs altogether. Adam Nasli, head broker analyst at BrokerChooser, said savers still have time to prepare before the new rules come into force. He urged people to review how their money is currently allocated and consider whether adjustments may be needed.
“Rather than waiting for the deadline to approach, use this period to take stock of how your cash is currently allocated within ISA wrappers, as it will no longer be a bulletproof tax shield,” Nasli said.
While Nasli notes the rules could successfully channel more long-term savings into productive investments, he warned that adding layers of bureaucracy risks alienating everyday savers. Around 66% of UK savers currently rely on Cash ISAs purely for their perceived safety and simplicity.
“Introducing additional layers of rules and charges risks undermining that simplicity, particularly for less experienced investors,” Nasli warned. “If the rules are perceived as uncertain or difficult to navigate, there is a danger that some may disengage from investing altogether or retreat further into cash-heavy positions.”
The long-term impact of the overhaul will depend on how clearly the changes are communicated and whether savers feel confident navigating the new rules. For now, the reforms signal a clear policy shift - away from cash savings and towards encouraging investment.
