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UK Capital Gains Calculator

Calculate your UK capital gains from your investment transaction history and generate a detailed calculation report. cgt-calc is intended for UK individual investors working from supported broker exports.

Supported sources include Charles Schwab, Freetrade, Hargreaves Lansdown, Interactive Brokers, Morgan Stanley, Sharesight, Trading 212, Vanguard, or a custom RAW format.

For supported transactions, the tool converts prices to GBP and applies the UK same-day, 30-day ("bed and breakfast"), and Section 104 holding rules. It prints a summary of disposal proceeds, allowable costs, gains, losses, dividends, and interest to the terminal and writes the full calculations to a PDF report.

cgt-calc reports the net gain from the transactions you supply and, for supported tax years, estimates the amount remaining after the annual exempt amount. It does not account for gains or losses outside those inputs, apply tax rates, work out your final tax bill, or submit a tax return. Some investment scenarios are not supported; check the relevant broker guide and the offshore funds limitations before relying on the result.

The PDF report includes separate Capital Gains and Interest and Dividends sections, with a summary at the end. Interest is grouped monthly per broker to keep reports concise, even for brokers that pay daily interest.

Example report

This compact 2025/26 example shows foreign-currency transactions, same-day and 30-day matching, Section 104 pooling, gains and losses, a dividend with overseas tax, and cash interest:

Example report, page 1 Example report, page 2 Example report, page 3

View full example report (PDF)

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