afterax

Capital gains

Capital gains

You keep

Share link includes your inputs in the URL.

£15,936

of a £20,000 gain · CGT bill £4,064 · effective 20.3%

2026/27 rates · Last checked · Sources visible below

Share matching not modelled

For shares, funds, ETFs and crypto, HMRC matching rules can change the gain: same-day acquisitions, 30-day bed-and-breakfast matching and the Section 104 pool are not calculated here.

Use this page for a simple disposal once you already know the matched cost basis. For trade-by-trade pooling, use a dedicated share matching calculator or an accountant.

Complex disposals note

This result is a single-disposal estimate. Multiple disposals, same-share matching, bed-and-breakfasting, pooled holdings, relief claims and non-residence can change the bill.

Gain breakdown

20.3% effective
Net to you

£15,936

AEA exempt

£3,000

CGT 18%

£49

CGT 24%

£4,015

How the gain is taxed

The gain stacks on top of your income for band determination.

£0£20,000

Total CGT £4,064

Split across two tax years?

Two AEAs of £3,000 means selling half before 6 April and half after could save tax.

Sell now (single tax year)

£4,064

Split across two years

£3,328

Splitting saves £736 by using two annual exempt amounts.

Where your tax goes

on £4,064 capital gains tax

Illustrative allocation only - UK taxes are not ring-fenced. Approximate share of UK central government spending, applied to your capital gains tax.

21%

£866

Welfare

12 weeks of welfare per citizen

21%

£849

Health

87 days of NHS care (per citizen)

12%

£484

State Pensions

2 weeks of state pension

11%

£439

National Debt Interest

10%

£419

Education

11 school days funded

6%

£224

Defence

Categories and shares from HMRC's 2024/25 Annual Tax Summary methodology (PESA 2025 + OBR March 2025). Last reviewed 2026-04-29.

See the full UK budget →

+ £788 across public order & safety, transport, business & industry and 6 more

Use this if

  • You have one UK capital gain to estimate for 2026/27.
  • You want to see the annual exempt amount and 18%/24% bands.
  • You are checking a simple shares, crypto or residential property disposal.

Not for

  • Multiple disposals with share pooling or 30-day matching.
  • Business Asset Disposal Relief, EIS/SEIS deferrals or trusts.
  • Non-UK residence, split-year treatment or mixed-fund cases.

Estimates for illustrative and educational purposes only. Calculations use HMRC published rates and are not regulated financial, tax, or legal advice. Verify against your own tax position before filing or making financial decisions.

Related calculators

Other UK tax tools that pair with this one.

Capital Gains Tax in the UK

CGT is paid on profits from selling assets: shares, crypto, second homes, business interests and more. October 2024 reforms raised the rates to 18% and 24% across most asset types, while keeping the £3,000 annual exempt amount.

  • What is the UK Capital Gains Tax allowance for 2026/27?

    The annual exempt amount is £3,000. Gains above that are taxable. The allowance can't be carried forward: if you don't use it in a tax year, you lose it.

  • What CGT rates apply for 2026/27?

    Gains on shares, crypto and other assets are taxed at 18% (basic rate) or 24% (higher/additional). Residential property has used 18%/24% since the October 2024 reform. Business Asset Disposal Relief is now 18% on the first £1m of qualifying lifetime gains, raised in stages from the historic 10% (10% → 14% in April 2025 → 18% from April 2026).

  • Can I split a gain across two tax years to save tax?

    Yes. Selling part of an asset before 6 April and the rest after gives you two £3,000 annual allowances. The Afterax CGT calculator shows the saving when this strategy applies to your gain.

  • What is the 60-day reporting rule for property?

    Disposals of UK residential property must be reported and the CGT paid within 60 days of completion using HMRC's Capital Gains Tax on UK Property service, which is separate from Self Assessment.

  • How does the 30-day rule affect crypto and shares?

    If you sell shares or cryptocurrency and buy back the same asset within 30 days, the new acquisition cost is matched against the disposal, preventing 'bed and breakfasting' to crystallise losses.

Sources & last reviewed

Updated for 2026/27 · last reviewed 1 May 2026 · view changelog →

Bands, thresholds and reliefs on this page come directly from the following official sources. Tax rates are checked against these references whenever a Budget or in-year change is announced.