The ISA vs GIA question used to be boring. A decade ago, the CGT annual allowance was over £12,000 and the dividend allowance was £5,000. You could hold a reasonable portfolio in a GIA and pay no tax. That world is gone. In 2026/27 the CGT exempt amount is just £3,000 and the dividend allowance is £500. For anyone with a serious portfolio, the ISA wrapper has never mattered more.
ISA vs GIA: The Core Difference
A Stocks & Shares ISA is a wrapper around your investments that tells HMRC to ignore them. No capital gains tax when you sell. No dividend tax on distributions. No interest tax on cash held inside. You do not even declare it on your self-assessment tax return. The only catch is a £20,000 annual contribution cap (2025/26 and 2026/27).
A General Investment Account (GIA), sometimes called a dealing account, is the same investments without the wrapper. Every sale triggers a potential CGT calculation. Every dividend is potentially taxable. There is no contribution limit, but there is also no protection.
| Feature | Stocks & Shares ISA | General Investment Account |
|---|---|---|
| Annual contribution limit | £20,000 (2026/27) | None |
| Capital gains tax | 0% | 18% basic / 24% higher on shares above £3,000 |
| Dividend tax | 0% | 8.75% / 33.75% / 39.35% above £500 |
| Interest tax | 0% | Up to 45% above personal savings allowance |
| Self-assessment needed? | No | Yes, if over thresholds |
| Asset range | ISA-eligible shares, funds, ETFs, bonds | Almost anything |
The 2026/27 UK Tax Numbers You Need to Know
These are the numbers driving every worked example below:
- CGT annual exempt amount: £3,000 (down from £12,300 in 2022/23)
- CGT rate on shares: 18% for basic-rate taxpayers, 24% for higher-rate and additional-rate taxpayers
- Dividend allowance: £500 (down from £2,000 in 2022/23)
- Dividend tax rates: 8.75% basic, 33.75% higher, 39.35% additional
- ISA allowance: £20,000 per adult per tax year
Both the CGT exempt amount and dividend allowance have been slashed in recent Budgets. This is not a theoretical tax any more — a £50,000 GIA throwing off a modest 3% dividend yield already exceeds the dividend allowance on its own.
Worked Example 1: £20,000 Portfolio
You have a £20,000 portfolio in a global equity index fund. It returns 8% per year, split roughly 2% dividend yield and 6% capital growth. After one year, your portfolio is worth about £21,600. Suppose you rebalance or take some profits, crystallising a £1,600 gain.
| Tax event | ISA | GIA (basic rate) | GIA (higher rate) |
|---|---|---|---|
| £400 dividends | £0 | £0 (within £500 allowance) | £0 (within £500 allowance) |
| £1,600 realised gain | £0 | £0 (within £3,000 exemption) | £0 (within £3,000 exemption) |
| Total tax | £0 | £0 | £0 |
At £20,000, both wrappers produce the same tax bill in a simple year — zero. So is an ISA pointless here? Not at all. The moment you add a second year of gains, rebalance heavily, or your dividend yield ticks above £500, the ISA starts to save real money. And once your portfolio grows past £20,000, you cannot move the excess into an ISA in a single year.
Worked Example 2: £50,000 Portfolio
You have £50,000 invested — say, three years of ISA contributions plus some growth. Your annual return is 8% (£4,000), with a £1,250 dividend yield (2.5%) and £2,750 capital growth. You rebalance once, realising £2,750 of gains.
| Tax event | ISA | GIA (basic rate) | GIA (higher rate) |
|---|---|---|---|
| £1,250 dividends (£500 allowance) | £0 | £65.63 (8.75% on £750) | £253.13 (33.75% on £750) |
| £2,750 gain (£3,000 exemption) | £0 | £0 (within exemption) | £0 (within exemption) |
| Total tax | £0 | £65.63 | £253.13 |
At £50,000, the higher-rate taxpayer loses £253 per year to dividend tax alone — and that is before any larger rebalancing. Over 20 years of compounding, that drag compounds into several thousand pounds of missed growth. The ISA version keeps 100% of its gains.
Worked Example 3: £100,000 Portfolio
You have £100,000 invested across a diversified portfolio. Yield is 2.5% (£2,500 dividends). You rebalance more actively and sell £15,000 of holdings, crystallising £5,000 of gains.
| Tax event | ISA | GIA (basic rate) | GIA (higher rate) |
|---|---|---|---|
| £2,500 dividends (£500 allowance) | £0 | £175.00 (8.75% on £2,000) | £675.00 (33.75% on £2,000) |
| £5,000 gain (£3,000 exemption) | £0 | £360.00 (18% on £2,000) | £480.00 (24% on £2,000) |
| Total tax | £0 | £535.00 | £1,155.00 |
A higher-rate taxpayer with a £100,000 GIA pays over £1,100 of tax per year in this scenario. Running that for 20 years, assuming the portfolio keeps growing, costs north of £25,000 in direct tax — plus the lost compounding on that tax drag. The same portfolio inside an ISA pays zero. This is why every pound of your £20,000 annual ISA allowance matters.
When a GIA Still Makes Sense
A GIA is not always a bad choice. There are a handful of genuine reasons to use one:
- You have already maxed your ISA. Once you have contributed £20,000 this tax year, the next pound has to sit somewhere. A GIA is usually the right destination until 6 April rolls around and you can Bed & ISA.
- You have maxed your pension too. If you have used the £60,000 annual allowance (or your tapered version), a GIA becomes your next wrapper option alongside things like a Lifetime ISA.
- You hold non-ISA-eligible assets. Certain niche investment trusts, individual bonds, or unlisted shares may not qualify for ISA. A GIA is the only listed option.
- You want short-term, flexible access without using ISA allowance. If you are holding for a house deposit and expect to spend the money within 12 months, the tax efficiency of an ISA barely matters. You may prefer to protect your allowance for long-term investing.
- Specific trust or business structures. Corporate accounts, trust accounts, and bare trusts use GIAs rather than ISAs.
Outside these cases, the ISA wrapper is almost always the better home for your money.
Bed and ISA: Moving a GIA Into an ISA
If you already have investments in a GIA and want to move them into an ISA, the process is called Bed and ISA. Most UK platforms offer it as a one-click service.
Here is how it works: your platform sells your GIA holdings and immediately repurchases the same investments inside your ISA. The buy and sell normally happen in the same trade, so you are not out of the market. Any gain on the sale still counts towards your £3,000 CGT annual exempt amount, so the strategy works best in chunks of roughly £20,000 to £25,000 per tax year.
If your embedded gains are larger than £3,000, you have two options: phase the Bed and ISA over multiple tax years, or pay the CGT to accelerate the move. At 24% CGT for a higher-rate taxpayer, paying tax now may still beat leaving the money in a GIA and paying CGT plus dividend tax every year for the next two decades. Use our ISA fee calculator to model the long-term cost of getting this wrong.
Funds vs Shares: A Tax Treatment Note
Inside a GIA, different holdings are taxed differently:
- UK-listed shares: Dividends taxed as dividend income, gains taxed as CGT. Straightforward.
- UK-authorised funds and ETFs with HMRC reporting status: Taxed the same way as shares — dividends on distributions, CGT on sale. Note that some ETFs also have "excess reportable income" you need to declare even if nothing is paid out.
- Non-reporting offshore funds: Gains are taxed as offshore income gains at income tax rates up to 45%, not CGT. This is a trap with certain US-domiciled ETFs.
- Accumulation units: Still taxed on dividends each year even though nothing is paid out — HMRC treats the reinvested income as received.
Inside an ISA, none of this matters. Every holding is tax-free regardless of share class, domicile, or distribution policy. This is another underrated benefit of the ISA wrapper for anyone holding global ETFs.
The Direction of Travel: Allowances Keep Shrinking
The CGT annual exempt amount has dropped from £12,300 in 2022/23 to £3,000 in 2024/25, and remains at £3,000 for 2026/27. The dividend allowance has fallen from £5,000 in 2016/17 to £500 today. Both cuts are worth tracking because they make ISA wrappers more valuable every year, not less. Every time HMRC trims a GIA allowance, your ISA becomes more precious.
For a full run-down of the best platforms to hold your ISA, see our best Stocks & Shares ISA UK 2026 guide and our capital gains tax guide for more detail on the CGT rules.
FAQ
Is a Stocks and Shares ISA always better than a GIA?
For almost every UK investor with room in their £20,000 ISA allowance, yes. An ISA is completely free from CGT and dividend tax. A GIA is subject to CGT at 18% or 24% and dividend tax at 8.75% or 33.75% once you exceed the shrunken annual allowances. The exceptions are specific trust structures, overseas income scenarios, and investors who have already maxed their ISA and pension.
What is the CGT allowance in 2026/27?
The CGT annual exempt amount is £3,000 per person for the 2026/27 tax year, unchanged from 2025/26. Gains above £3,000 are taxed at 18% for basic-rate taxpayers and 24% for higher-rate and additional-rate taxpayers on shares and funds.
What is a Bed and ISA?
Bed and ISA is the process of selling investments in a GIA and immediately rebuying them inside your Stocks and Shares ISA in a single operation. It uses your £20,000 annual ISA allowance to move taxable holdings into a tax-free wrapper. Any gain on the sale still uses your CGT annual exempt amount, so most investors phase it over multiple tax years to stay below £3,000 per year of gains.
Are funds and shares taxed differently in a GIA?
UK-authorised funds and ETFs with HMRC reporting status are taxed like shares — CGT on gains and dividend tax on distributions. Non-reporting offshore funds are taxed as offshore income gains at income tax rates up to 45%. Inside an ISA, none of these rules apply because everything is tax-free.
Does a GIA ever make sense over an ISA?
A GIA makes sense when you have already used your £20,000 ISA and £60,000 pension allowances, when you hold assets that are not ISA-eligible, or when you are holding money short-term where the wrapper choice does not affect your tax bill. For long-term investing, the ISA almost always wins.