ukcapitalgains

Capital Gains Tax Guides

Simple guides to UK Capital Gains Tax on shares, written in plain English with worked examples.

Illustration of a rising share price with the gain above a threshold highlighted

How Capital Gains Tax on Shares Works

What CGT is, the £3,000 allowance, the 18% and 24% rates, HMRC's matching rules and how to report, with simple examples.

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Illustration of stacks of shares pouring into a single pool with an average level

Section 104: How to Work Out the Average Cost of Your Shares

How HMRC pools your shares at an average cost, which fees count, and how to work out the cost of the shares you sell, step by step.

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Illustration of a timeline where a share sold is matched with one bought back within a highlighted 30-day window

The 30-Day Rule for Shares (Bed and Breakfasting) Explained

What happens if you sell shares and buy them back within 30 days, why it can wipe out the gain you meant to use, and the legal alternatives.

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Illustration of a blank tax form with a ticked box being submitted

How to Report Capital Gains on Shares (SA108)

Whether you need to tell HMRC, which boxes to fill in on the SA108 capital gains pages for shares, and the deadlines, with a worked example.

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