290 – Net capital losses from other years
If you are reporting a taxable capital gain on line 139, you can deduct the net capital losses you sustained before 2019 on the disposition (sale, transfer, gift, bequest, etc.) of property other than personal-use property or precious property, provided you did not deduct them in a previous year. To claim the deduction, complete form TP-729-V, Carry-Forward of Net Capital Losses, and enclose it with your return.
If you are deducting net capital losses from other years, see point 9 in the instructions for line 276 and complete Schedule N.