Under new government proposals, cash held within a Stocks and Shares ISA could soon lose its tax-free status on interest earned, marking a significant shift for savers. This move, currently in a consultation phase until 27 June 2026, aims to realign ISAs with their original purpose of encouraging long-term investment.
What's Changing and When
Currently, any interest accrued on cash held within a Stocks and Shares ISA benefits from the same tax-free wrapper as investment gains. However, the government is proposing to end this, meaning such interest would become subject to income tax, much like interest earned in a standard savings account. This change, if implemented, would apply not only to new cash deposited but also to existing cash balances within these ISAs.
It's crucial to understand that this is a proposal. The government's consultation period concludes on 27 June 2026, after which a decision will be made. Therefore, the change is not yet effective, but its potential impact warrants immediate attention from savers.
Why the Change?
The government's rationale, as reported by Money Saving Expert, is twofold. Firstly, it seeks to ensure ISAs are primarily used for their intended purpose: encouraging long-term investment in stocks and shares. This suggests a desire to prevent individuals from 'parking' significant cash sums in Stocks and Shares ISAs purely for the tax-free interest, rather than engaging with equity markets.
Secondly, the proposals aim to simplify ISA rules. By bringing the treatment of cash in Stocks and Shares ISAs in line with Junior ISAs (JISAs) and Child Trust Funds (CTFs), the government hopes to create a more consistent regulatory landscape across different ISA products.
Who is Affected?
This proposal directly impacts individuals who hold cash within a Stocks and Shares ISA. This includes those who keep a portion of their ISA allowance in cash for liquidity, or while awaiting investment opportunities. It's particularly relevant for those with substantial cash holdings in these accounts, as their interest earnings could become taxable.
Crucially, this change would not affect other popular ISA wrappers:
- Cash ISAs: All interest remains entirely tax-free.
- Lifetime ISAs (LISAs): Cash interest within a LISA, used by first-time buyers and for retirement savings, would continue to be tax-free, alongside the 25% government bonus on contributions up to £4,000 per year.
- Innovative Finance ISAs (IFISAs): Interest earned here would also remain tax-free.
What this means for you
If these proposals go ahead, any interest you earn on cash held within your Stocks and Shares ISA would be added to your total income for tax purposes. This means it could erode the value of your Personal Savings Allowance (£1,000 for basic rate taxpayers, £500 for higher rate taxpayers), potentially pushing more of your standard savings interest into a taxable bracket.
Scenario: The Impact on Your Savings
Consider a higher-rate taxpayer with £10,000 in cash within a Stocks and Shares ISA, earning 4% interest. Currently, that £400 interest is tax-free. Under the new proposals, that £400 would be added to their taxable income. If they've already used their £500 Personal Savings Allowance (PSA) from other savings, this £400 would be taxed at their marginal rate, potentially 40%, costing them £160 in tax. For a basic rate taxpayer who has used their £1,000 PSA, the £400 would be taxed at 20%, costing £80.
What to do Right Now
- Review your Stocks and Shares ISA holdings: Assess how much cash you currently hold within these accounts.
- Consider alternatives for cash: If you're holding cash for purely savings purposes, a dedicated Cash ISA remains the most straightforward tax-free option for interest. For first-time buyers, a Lifetime ISA offers a 25% government bonus on contributions up to £4,000 per year, alongside tax-free interest.
- Engage with the consultation: If you feel strongly about the proposals, you can submit feedback to the government before the 27 June 2026 deadline.
- Stay informed: Keep an eye on official announcements following the consultation period for definitive decisions.
The Other Side: Government's Perspective
While some savers may view this as an unwelcome tax grab, the government frames it as a measure to ensure the integrity and intended purpose of the Stocks and Shares ISA. The argument is that these accounts are designed for investment, and tax-free cash interest encourages a use case not aligned with that objective. Bringing the rules in line with JISAs and CTFs also suggests a push for greater consistency across the ISA family.
Where to Get Help
For personalised advice on your savings and investment strategy, particularly in light of potential tax changes, consider speaking to an independent financial adviser. They can help you navigate the various ISA options and ensure your money is working as efficiently as possible for your individual circumstances.
Sources
- Money Saving Expert — Savers to be charged on cash interest in stocks and shares ISAs under new plans
This is not financial advice. Seek independent financial guidance. Interest on standard accounts may be subject to tax above your Personal Savings Allowance.