Philip, thank you for your reply.
In general terms, if you sell shares in a tax year and these sales have resulted in a combination of realised gains and losses, then you can offset the losses aginst the gains and the net posttion is reported on your tax return.
If it results in an overall gain, then you claim you annual exempt amount against it and the balance is chargeable to CGT at 18%, 28% or a combination of both depending on your total taxable income in the year.
If there is a net loss, then you still report the loss to HMRC for it to become an allowable loss for offset against gains in future years.
More information on how to claim a loss and the time limits for claiming are covered herehttp://www.hmrc.gov.uk/cgt/intro/losses.htm
If you are investing in shares as an investment club, the individual member is charged to tax on their proportionate share of any gains and is entitled to relief in respect of any share of capital losses.
I hope this is helpful and answers your question.
If you have any other questions, please ask me before you rate my service – I’ll be happy to respond.