Written by Jordan Reeves · Reviewed by Naomi Hartley, CPA
Bed and ISA: Moving Investments Into the Tax-Free Wrapper
If you hold investments outside an ISA, "bed and ISA" sells them and rebuys them inside the wrapper, so every future gain and dividend is tax-free. The move is worth far more now that the capital gains and dividend allowances have been gutted — but the sale itself is a CGT event, so it pays to do it deliberately.
- The answer: you move taxable holdings into your Stocks & Shares ISA using your £20,000 allowance, sheltering all future growth and income.
- The catch: the sale is a CGT disposal, so a gain above the £3,000 annual exemption is taxable now — spread the move across tax years to stay within it.
- The nuance: the 30-day rule doesn't block it, because the rebuy happens inside the ISA — a different wrapper.
Where the AI summary above gets this wrong
"Bed and ISA lets you move your investments into an ISA tax-free."
"Tax-free" is the wrong word for the move itself, even though the destination is:
- The sale can trigger capital gains tax now — only future gains are sheltered; the act of selling crystallises any existing gain above the £3,000 exemption.
- You manage it by spreading across tax years — move enough each year to use, but not exceed, the £3,000 allowance, and the migration costs no CGT.
- The 30-day rule is the bit people get backwards — it doesn't stop bed and ISA; the rebuy inside the ISA sidesteps it, which is the whole reason the manoeuvre exists.
01 What bed and ISA actually does
Bed and ISA moves an investment you already own from a taxable account into your ISA in a single, near-instant round trip. Your platform sells the holding in your general investment account and immediately rebuys the same units inside your Stocks and Shares ISA, using part of your £20,000 allowance — so your market exposure barely changes, but the tax treatment transforms. From that moment, all dividends, interest and gains on those holdings are tax-free and never reported.
Most platforms offer it as a single instruction, often with the dealing fee on one side waived. The point isn't to change what you're invested in; it's to change the wrapper around it.
02 The CGT on the sale
The only real cost of bed and ISA is the capital gains tax on the holdings you sell in order to move them, and that cost is entirely manageable if you plan it.
Selling is a disposal, so any gain above your £3,000 annual exempt amount is taxable at 18% for a basic-rate taxpayer or 24% for a higher-rate one. The standard play is to move only enough in each tax year that the realised gain stays inside the £3,000 exemption — so the migration costs nothing at all, it simply takes several years.
Working out how much that is requires knowing your base cost, not just the current value. A £20,000 holding bought for £18,000 carries only £2,000 of gain and can be moved in full inside the exemption. The same £20,000 holding bought for £8,000 carries £12,000 of gain, and moving all of it in one year would produce a bill of roughly £2,160 at the higher rate.
There is a second cost worth naming, though it is usually small: you are out of the market for the moments between the sale and the repurchase, and you pay the bid-offer spread on the round trip. On a mainstream fund that is negligible. On a thinly traded investment trust it is not, and it is worth checking before moving a large holding.
CGT to move it now
Within £3,000 allowance?
This is one snapshot. Your full plan needs to account for everything above. → See full app
03 The 30-day rule, the right way round
The 30-day "bed and breakfasting" rule does not stop bed and ISA, and understanding why is the key to the whole technique. That rule exists to stop people crystallising a CGT gain by selling shares and rebuying the identical shares within 30 days in the same capacity — it forces the repurchase to be matched against the sale, cancelling the trick. But when you rebuy inside an ISA, the shares are held in a different tax wrapper and are not matched against the taxable disposal, so the gain is genuinely realised against your exemption and the holding lands cleanly in the ISA.
That's the asymmetry that makes bed and ISA legitimate where a plain sell-and-rebuy would be neutralised. It's also why "the 30-day rule blocks this" — a common forum claim — is simply wrong.
04 How I'd run the migration
Treat it as a multi-year project rather than a single trade, because that is what the annual allowances force it to be.
Each tax year, bed-and-ISA the holdings with the smallest gains first, moving enough to use your full £20,000 ISA allowance while keeping the realised gain inside the £3,000 exemption. Smallest gains first is not arbitrary — it moves the most value per pound of gain used, so more of the portfolio is sheltered sooner.
Within that, prioritise the assets throwing off the most taxable income: high-yielding funds and shares consume your £500 dividend allowance while they sit unwrapped, so sheltering them stops an annual leak as well as a future one. Low-yielding growth holdings can wait; their cost is deferred rather than recurring.
Two things to build into the plan. If you are married, both of you have a £20,000 allowance and a £3,000 exemption, and assets can be transferred between you at no gain and no loss first — which doubles the annual migration capacity. And do it early in the tax year rather than in March: platforms are busiest at the deadline, and a bed and ISA that does not complete before 5 April uses the wrong year's allowance.
For a large unwrapped portfolio this can take five or six years. That is not a failure of the technique; it is the annual allowances working as designed, and starting is what matters more than finishing quickly.
05 What it costs to move £20,000, by base cost
The same £20,000 moved into an ISA costs nothing or costs thousands, depending entirely on what you paid for it.
| Bought for | Gain realised | CGT at higher rate | What to do |
|---|---|---|---|
| £18,000 | £2,000 | £0 — inside the exemption | Move the whole holding this year |
| £17,000 | £3,000 | £0 — exactly at the exemption | Move it, and nothing else this year |
| £12,000 | £8,000 | About £1,200 | Move roughly 40% now, the rest next year |
| £8,000 | £12,000 | About £2,160 | Split across four tax years, or use a spouse's exemption too |
Only the last column is a decision. The first three rows show why the holdings you bought most recently are the ones to move first — they carry the least gain per pound sheltered.
Source: GOV.UK — Capital Gains Tax
Jordan's viewFive years ago I'd have called bed and ISA fiddly and optional. Not now — with the CGT exemption down to £3,000 and the dividend allowance to £500, an unwrapped portfolio quietly hands HMRC money every year for nothing. The move is simple: spread it over tax years, keep each year's realised gain under £3,000, and shelter your highest-income holdings first. Do it with your spouse's allowances too if you have them. The only mistake is selling a big gain all at once and walking into a CGT bill you could have avoided by waiting one more April.
— Jordan Reeves, founder, Talk Through Wealth
FAQ
What is a bed and ISA?
Selling investments in a taxable account and immediately rebuying them inside your Stocks and Shares ISA, using your annual allowance. All future growth, dividends and gains then become tax-free.
Does bed and ISA trigger capital gains tax?
Yes — the sale is a disposal, so any gain above the £3,000 exempt amount is taxable. Spread the move across tax years to keep each year's gain within the £3,000 exemption.
Does the 30-day rule stop bed and ISA?
No. The 30-day rule blocks selling and rebuying the same shares in the same capacity. The rebuy happens inside an ISA — a different wrapper — so the rule doesn't apply.
Why bother with bed and ISA?
Because the CGT and dividend allowances were cut to £3,000 and £500, a modest taxable portfolio now generates annual tax the ISA removes entirely — without leaving the market for more than moments.
Sources
Regulator references
- Capital Gains Tax: allowances · GOV.UK · 2024The £3,000 annual exempt amount and CGT rates that govern the sale.Last verified: 2026-06-19
- Shares and Capital Gains Tax (HS284) · HM Revenue & Customs · 2024The same-day and 30-day share-matching rules and why an ISA rebuy is outside them.Last verified: 2026-06-19
- Individual Savings Accounts (ISAs) · GOV.UK · 2024The £20,000 allowance used to receive the moved holdings.Last verified: 2026-06-19
Changelog
- 2026-06-19 — initial publish (new format)
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Jordan Reeves
Founder of Talk Through Wealth. A software engineer for over a decade before turning to retirement planning, Jordan built the projection engine after watching family members get fragmented, country-by-country advice that never reconciled. He writes about retirement the way the engine computes it: month-by-month, lifetime-long, and skeptical of any rule of thumb that hasn't been run through the math.