Twofish

Hi, Can you clarify the following? Year 1 2 Share sales leading to CGT losses of £1000 and 1500 Capital gain on 3rd sale below year 1 allowance so no claim made for losses Year 2 Capital gains made of £6500 CGT allowance of £6000 Assume my options are either: a) pay the CGT on £500 or b) use losses from Year 1 to offset the CGT. If I choose option b do I have to use all the losses from Year 1 or can I use the losses on a single sale and leave the £1500 to be claimed in future. Once losses are claimed do they have to be used in the next tax year where gains are made? Thankyou