ShareCalc

Share Capital Gains Tax (CGT) Calculator

This calculator helps first-time share sellers understand and calculate their UK capital gains tax liability on a single share disposal.
If you need to calculate CGT for more complex scenarios or multiple disposals, you can enter your transactions into ShareCalc and let it do the hard work for you.

UK CGT and Share Identification Rules

UK capital gains tax for shares uses share identification rules, which treat all unclogged shares of the same class in the same company across all accounts as a single asset. Shares disposals are first matched with acquisitions on the same day, secondly with any acquisitions in the 30 days after, and finally are matched with an average cost holding called a section 104 holding (s104).
This calculator is suitable if:
  • You have never sold shares before the disposal
  • You have not or will not acquire shares on the day of the disposal or in the 30 days after
This calculator will:
  • Calculate your capital gain or loss on this first disposal
  • Show the breakdown of all components affecting your calculation
  • Help you understand your updated s104 holding balance after the sale

How to use this calculator

1. Gather your acquisition history: Collect records of all unclogged shares you own in this company from all broker accounts.
2. Convert to sterling: Ensure all acquisitions and the disposal are converted to GBP using the exchange rate at the time of each transaction.
3. Enter share quantity: Input the total number of shares you owned before the disposal in the Number of Shares Owned Before Disposal box.
4. Enter acquisition details:
• Sum the total purchase price plus allowable expenses in the Acquisition Cost + Expenses box
• Enter any equalisation amounts in the Equalisation box
• Enter the sum of any reinvested distributions from accumulating shares and any excess reportable income (ERI) in the Notional Distributions box

Note:

  • Reinvested distributions and ERI need to have been taxed to be used in the CGT calculation and should be entered gross, without any adjustments for equalisation.
  • If you dispose of an offshore reporting fund after a reporting period's end date and before that period's distribution date (when you are deemed to receive the ERI), you still include that period's ERI for the CGT calculation.
5. Enter disposal details:
• Input the number of shares sold in the Number of Shares Disposed of box
• Enter the total proceeds in the Disposal Proceeds box
• Enter any allowable expenses for the disposal in the Disposal Costs box
6. Click "Calculate" to see your capital gain/loss and updated s104 holding information.

For more complex calculations, tracking multiple disposals, and automatic currency conversion, try our comprehensive CGT calculator at ShareCalc.

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UK Capital Gains and Investment Tax Calculator

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