Bed and ISA is financial adviser shorthand for a simple annual job: moving investments from an ordinary taxable account into an ISA. The name is odd and the job is dull. Done every year, it can build a substantial portfolio free of income tax and capital gains tax.
If your adviser has suggested you 'bed and ISA' some of your investments, you might wonder what sleep has to do with it. The answer lies in an old tax trick.
Until 1998, investors could sell shares one day and buy the same shares back the next. The practice was known as bed and breakfasting. The aim was to use up that year's capital gains tax allowance while keeping the same investment, which cut the taxable gain on any later sale. The trick was entirely legal. In March 1998 the government stopped it working, with a rule covering shares bought back within 30 days.
ISAs arrived on 6 April 1999. Selling investments you hold outside an ISA and buying them back inside one soon became known as bed and ISA. But unlike its predecessor, it is still allowed. HMRC's own guidance for ISA providers sets out how it works, under the formal name 'Share Exchange'.
Matt Frary APFS, Director and Chartered Financial Planner at rockwealth Norwich, has arranged bed and ISA for clients for 25 years, and several of them now hold sizeable ISA portfolios as a result, built in annual instalments that looked trivial at the time.
How bed and ISA works
Bed and ISA has three steps. You sell up to £20,000 of holdings from a general investment account, the ordinary taxable account for investments held outside a pension or ISA. You pay the proceeds into a stocks and shares ISA. Then you buy back the same investments, or something close to them, inside the ISA. Matt keeps the investment strategy identical on the other side of the move.
Why sell something only to buy it straight back? Because, apart from some shares from employee share schemes, you can't move existing investments straight into an ISA. You have to sell them and pay in cash.
But the sale can trigger a tax bill. HMRC's guidance confirms that 'the sale of the investments is a disposal for capital gains purposes'. Any gain above the capital gains tax allowance, £3,000 in the 2026/27 tax year, is taxable in the tax year you sell.
Say you move £20,000 of a fund that has gained £4,000 since you bought it. Assuming no other gains that year, only £1,000 of the gain is taxable after the £3,000 allowance, and the bill for a higher-rate taxpayer is £240.
Platforms handle the mechanics differently. On some, the sale and the repurchase are processed together. On others, the money sits in cash, out of the market, for a short time. Dealing charges vary too. Worth checking before you start, not after.
Why holding investments outside an ISA costs more than it did
Since 2022, three tax changes have made holding funds and shares outside an ISA markedly more expensive, and moving them inside correspondingly more valuable.
Capital gains first. On HMRC's published rates, the capital gains tax allowance was £12,300 in 2022/23. From 2024/25 onwards it has been £3,000, around a quarter of what it was. Rates rose too, from ten and 20 per cent to 18 and 24 per cent on 30 October 2024. Dividends got the same treatment. The dividend allowance stood at £2,000 as recently as 2022/23, dropped to £1,000 in 2023/24 and has been £500 since 2024/25. On 6 April 2026 the rates rose again, to 10.75 per cent for basic-rate taxpayers and 35.75 per cent for higher-rate taxpayers.
A single sale shows what has changed. A higher-rate taxpayer who makes a £10,000 gain in the 2026/27 tax year pays £1,680, because £7,000 of it sits above the £3,000 allowance and is taxed at 24 per cent. In 2022/23 the £12,300 allowance would have covered the whole gain and the bill would have been nothing. On dividends, every £1,000 above the £500 allowance costs a higher-rate taxpayer £357.50.
Then there's the paperwork. Outside an ISA, you may have to report income and gains to HMRC, year after year. An ISA takes that chore away.
'It keeps everything simple,' says Matt. 'There's no income tax, no dividends and no capital gains tax to report every year.'
What 25 years of bed and ISA can add up to
Used in full every year, the ISA allowance turns small moves into a large tax-free sum, and a couple with two allowances can reach roughly double.
The allowance itself has grown over the past 25 years. It was £7,000 in 2001/02 and has been £20,000 since 2017/18. So what would someone have today if they'd used all of it each year since 2001/02?
What full use of the ISA allowance could have built by April 2026
| One person | A couple | |
|---|---|---|
| Paid in, 2001/02 to 2025/26 | £332,560 | £665,120 |
| Value at four per cent growth a year | £512,000 | £1,025,000 |
| Value at five per cent growth a year | £576,000 | £1,152,000 |
| Value at six per cent growth a year | £649,000 | £1,299,000 |
Illustration only. Assumes the full allowance was paid in at the start of every tax year and grew at a steady rate, before charges. Real returns are uneven and not guaranteed. Figures rounded to the nearest £1,000.
Real life was lumpier than the rows suggest. Markets fell hard in 2008, and again in early 2020. And the illustration assumes the money was there to move every April. Most savers don't use the whole allowance: HMRC's figures show that 28.8 per cent of ISA subscribers paid in the maximum in 2023/24.
The same investments would have risen and fallen in a taxable account too, so none of the growth in the table comes from bed and ISA itself: what it decides is how much of that growth you keep, and whether any of it ever has to go on a tax return.
'Over the years, someone could have built up anywhere from £500,000 to £1 million in ISAs, completely tax-free,' says Matt.
His range maps onto the table. The bottom is roughly what one person's allowances could have produced at modest growth, and the top is where a couple using both could have arrived. One of his clients has passed £1 million on their own.
What surprises clients, he says, is how far a consistent process and compounding tax-free returns can take them.
Two things need saying about the phrase 'tax-free'. ISA income and gains escape income tax and capital gains tax, but ISA investments still form part of your estate for inheritance tax. And from 6 April 2027, interest paid on cash held inside a stocks and shares ISA will face a flat 22 per cent charge. The ISA provider will deduct it, under rules HMRC published in September 2026 that also cover money market funds held in an ISA. So money moved in through bed and ISA is better invested than left sitting as cash.
How to make bed and ISA an annual habit
'It's such an obvious, easy win every year,' says Matt. 'It just requires discipline.'
Discipline is the whole of it. Bed and ISA pays off through repetition, so the aim is to make it a fixed annual task rather than a decision you reopen every spring. Early in the tax year is the natural time. The ISA allowance resets on 6 April, and HMRC's guidance for ISA managers is explicit that an investor who hasn't used it all 'cannot carry forward the difference and add it to the subscription limit for the next year'.
A year missed is gone for good.
A steady annual move also keeps the gain you take each year small, closer to the £3,000 allowance. Leave everything in the general investment account and the gain keeps growing, until one large sale brings one large tax bill.
Couples have more to work with than they often realise. Married couples and civil partners each have their own £20,000 ISA allowance and their own £3,000 capital gains allowance. HMRC's rules also let spouses and civil partners who live together pass assets to each other without a capital gains tax charge. That lets a couple use both sets of allowances.
What goes inside the ISA matters too. A tax shelter doesn't turn a poor investment into a good one, so the contents are best kept low-cost and broadly diversified. And for many investors a pension comes first, because contributions attract tax relief, so an ISA tends to complement a pension rather than replace it.
As for anyone starting late, there's no time like the present, Matt says. It's a shame when previous years' allowances have gone unused, though among his clients that's rare.
From overnight trick to annual habit
Bed and breakfasting was a one-night manoeuvre. Bed and ISA works on a different timescale. Its value comes from repeating a dull job every year, for decades, until most of your investments sit inside an ISA. This year's allowance runs until 5 April.
'I think saving every penny our clients can in tax-efficient shelters such as ISAs is fundamental,' says Matt.
If you'd like to check whether bed and ISA fits your wider plan, and whether you and your partner are making full use of your allowances, Matt Frary at rockwealth Norwich can help.
