declaring and claiming a capital loss to be deducted from capital gains in the same year

In the 23/24 tax year I sold various shares. Some made gains and some made small losses, which I wished to be deducted from the capital gains on which tax was payable. All the shares were listed. I filled in the relevant boxes declaring number of disposals, total gains (before losses) and then total losses in Box 27. I also provided detailed additional information about all the sales, gains and losses on a separate sheet. I thought that was sufficient for HMRC to deduct the losses in box 27 from the total taxable gains, but was subsequently told that I should also have put the losses in Box 46 if I wanted HMRC to deduct them from the taxable gains made in the same year. Is that correct? I am retired so have no earnings and my only other income is from a SIPP and dividends. I would like to make sure that any future losses are deducted from any taxable gains but don't want to put the losses from Box 27 in Box 46 if that is for something else.

PS My reading of the tax form was that Box 46 is for trading losses eg if I ran a business and made less in turnover than I spent on costs. I do not think of capital losses as a trading loss because my investments were personal not part of a business. Was the person who told me I should put current year capital losses in Box 46 correct or not? I don't think I've ever done that before but in the past, losses I put in Box 27 were deducted by HMRC from my capital gains. Please help. I expect to incur more capital losses in 2024/25 and want to know how I should correctly declare them (box 27) and ensure you deduct them from any gains I may make.

Hi,
Box 46 is only for other trading losses that can be used after setting off in year capital losses, so if you only have the in year losses, box 46 should be left blank.
Thank you.

Hi ,
 

By putting the losses in at box 27 this will automatically reduce any gain. No entry is required at box 46 for capital losses . Thank you .