How does a Bed and ISA transaction help reduce Capital Gains Tax?

Full answer

Bed and ISA is a well-established strategy for investors who have built up substantial holdings outside a tax-efficient wrapper and want to move them inside one gradually, without triggering an unnecessary immediate tax bill. **How the transaction works** You sell (some brokers call this "bedding out") investments held in a general investment account, then immediately buy back the same or a similar investment inside a Stocks and Shares ISA, using your annual ISA subscription allowance (£20,000 for 2026/27) to fund the repurchase -- the net effect is that the investment ends up inside the ISA, sheltered from future Capital Gains Tax and dividend tax. **Using your CGT annual exempt amount** Selling the investment outside the ISA realises a capital gain (or loss), which uses some or all of your annual Capital Gains Tax exempt amount for the year -- since this exempt amount is much lower than it used to be, many investors doing Bed and ISA transactions will actually generate a taxable gain if the profit exceeds the current allowance, so it is important to check the numbers, not simply assume the transaction is automatically tax-free. **Worked example** An investor holds £15,000 of shares outside an ISA, originally bought for £10,000, giving an unrealised gain of £5,000. If they sell these shares and their only other capital gain for the year is nil, the £5,000 gain may be fully covered by their annual CGT exempt amount, meaning no CGT is due on the sale. They then use their ISA allowance to repurchase the same shares inside a Stocks and Shares ISA -- from that point onwards, any future growth, dividends, and eventual sale of those shares inside the ISA are completely free of Capital Gains Tax and dividend tax. **Spreading larger holdings across multiple tax years** Investors with holdings much larger than a single year's combined ISA allowance and CGT exempt amount often spread Bed and ISA transactions across several tax years, moving a portion each year to manage the total capital gain realised (avoiding exceeding the CGT exempt amount unnecessarily) while also respecting the annual £20,000 ISA subscription limit. **The bed and breakfast rule and why it does not block Bed and ISA** HMRC's "bed and breakfasting" anti-avoidance rule (the 30-day rule) normally prevents you from selling a share and buying back an identical share within 30 days purely to crystallise a loss or gain while keeping the same holding -- however, this rule is specifically not breached by Bed and ISA transactions, because moving shares into an ISA is treated differently by HMRC from simply reselling into the same account, so the sale and purchase are both recognised for tax purposes even though the investment itself does not change. **Costs to consider** Bed and ISA transactions typically involve selling and buying costs (dealing charges, and potentially the bid-offer spread on the investment), so it is worth checking your broker's specific Bed and ISA fee structure, since some platforms offer reduced or combined fees for this specific type of transaction compared with two entirely separate trades. **Practical tip** Calculate your expected capital gain on the specific holdings you plan to move BEFORE doing a Bed and ISA transaction, checking it against your remaining annual CGT exempt amount for the year, and consider spreading a large portfolio across several tax years to avoid an unexpected CGT bill while gradually sheltering more of your investments inside ISAs.

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