By UK Tax Drag · Reviewed 3 October 2026

Your disposal

Sale proceeds

Allowable cost of the shares sold Use the pooled or matched cost for the shares disposed of, not the total cost of your whole account.

Buying costs included in the gain calculation

Selling costs included in the gain calculation

Losses carried forward from earlier years Only the amount needed to bring the gain down to the £3,000 annual exempt amount is used; the rest carries forward.

Your taxable income for the year before this gain This should already be after Personal Allowance and any income-tax reliefs.

Optional note

Estimated Capital Gains Tax due on this share disposal

£0 Estimated disposal cash after sale costs and CGT: £0

Gross gain before losses and allowance£0

Taxable gain after losses and annual exempt amount£0

Gain taxed at 18%£0

Gain taxed at 24%£0

Annual exempt amount used£0

Basic-rate band left before the gain£0

Net cash after CGT£0

What this means

The rate on share gains now depends on how much of the basic-rate band is still unused once your taxable income has taken its slice. The annual exempt amount should normally be used against the highest-taxed gains first.

Rules checked on 3 October 2026 against GOV.UK: Capital Gains Tax rates (18% and 24%), GOV.UK: Capital Gains Tax allowances (£3,000), GOV.UK: Capital Gains Tax losses and GOV.UK: selling shares in the same company (pooling and matching).

Worked examples

See it on real numbers

Three Capital Gains Tax scenarios showing how the 18% and 24% rates, the £3,000 annual exempt amount and your other income fit together in 2026/27.

CASE 1

Hannah — basic-rate earner with £8,000 of GIA gains

Salary £35,000. Sold £40,000 of an emerging-markets ETF held in a general investment account, originally bought for £32,000.

Inputs

Gain: £8,000
Other income: £35,000
AEA used: 0

Result

CGT due: £900. After the £3,000 annual exempt amount, £5,000 is taxable. Her taxable income is £22,430 (£35,000 less the £12,570 Personal Allowance), which leaves £15,270 of the £37,700 basic rate band, so the whole £5,000 is taxed at 18%.

Takeaway. Had Hannah made a £20,000 gain instead, £17,000 would be taxable: £15,270 at 18% and £1,730 at 24%. Spreading disposals over more than one tax year uses more than one annual exempt amount and, for a basic-rate taxpayer, more than one year of basic rate band.

CASE 2

Sam — higher-rate earner with £15,000 of crypto gains

Married, salary £75,000. Sold ETH for £25,000, originally bought for £10,000. No other gains this year.

Inputs

Gain: £15,000
Other income: £75,000
AEA: £3,000

Result

CGT due: £2,880. After the £3,000 annual exempt amount, £12,000 is taxable, all at 24% because his income already uses the basic rate band.

Takeaway. Gifts between spouses or civil partners who live together are free of CGT, and the partner receiving the asset takes on its original cost. If Sam had given half the ETH to his wife before the sale, each would have a £7,500 gain and £4,500 taxable after their own annual exempt amount: £1,080 each at 24% (£2,160 in total), or £1,890 in total if her £4,500 fell within her basic rate band. The ETH she received, and the money from selling it, would then be hers.

CASE 3

Mike — additional-rate earner with £40,000 of fund gains

Salary £180,000. Selling £100,000 of an old general investment account holding originally bought for £60,000.

Inputs

Gain: £40,000
Other income: £180,000
AEA: £3,000

Result

CGT due: £8,880. After the £3,000 annual exempt amount, £37,000 is taxable at 24%.

Takeaway. Selling half the holding in one tax year and half in the next, with the same rates and allowance, would use two annual exempt amounts: two £20,000 gains leave £17,000 taxable each, £8,160 in total, £720 less. Selling in the general account to buy the same fund back inside an ISA (Bed and ISA) is still a disposal for CGT; the ISA allowance is £20,000 a year, and gains made inside an ISA are not taxed.

Illustrative examples for education only, not personal advice. Figures are rounded and use 2026/27 rates.

▸ How we calculate this — CGT on listed shares + funds

Method — 2026/27 tax year

Formula: Gain = disposal proceeds − allowable cost (using s.104 pooled cost for the same class of shares) − allowable expenses (broker fees, stamp duty on purchase). Then deduct the £3,000 annual exempt amount before applying CGT rates.

2026/27 CGT rates on shares: 18% on gains falling within your unused basic-rate band, 24% above. (Same rates as residential property since the October 2024 Budget aligned the regimes.)

Pooling: shares of the same class in the same company form a single ‘s.104 pool’. Average cost per share = total cost ÷ total shares in pool. Same-day and 30-day matching rules apply for disposals.

What we don't model: Business Asset Disposal Relief (18% on qualifying disposals from 6 April 2026, lifetime limit £1m), investors’ relief, EIS deferral, and bed-and-spouse / bed-and-ISA mechanics — those need bespoke handling, see our CGT guides.

Data sources

Reviewed against 2026/27 thresholds. We update when HMRC publishes rate changes — tracked in the changelog. Found an error? See corrections policy.

About this calculator

Last reviewed: October 2026. Reviewed by the Editor against current official guidance for 2026/27.

Verified against: gov.uk — Capital Gains Tax on shares (checked on the last review date above).

Source: calculator JavaScript is unminified at /assets/ — see Open methodology for how to verify the math. Updates tracked in the changelog.

Spotted an error? Report it. Confirmed errors are corrected under the corrections policy.

Disclaimer: This tool gives a guideline estimate using current published UK rates and thresholds. It is general information, not personal financial, tax, or legal advice. Verify the figures against your own circumstances, the latest gov.uk guidance, and a qualified adviser before acting. UK Tax Drag accepts no liability for decisions made on the basis of these calculations.

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Pages are checked against the primary sources listed on each page and reviewed by the Editor; corrections are logged in the changelog. Pages are drafted with the help of AI tools (how AI is used). No affiliate revenue. No sponsored content. No paid placements.

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UK Tax Drag is an independent publication by Finsolve Consulting Limited, not affiliated with or endorsed by HMRC, GOV.UK or any government body.

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