Can an individual use tax loss carry back to offset capital gains in the previous year?

[pk]

what type of tax loss ---- generally loss/credits can only be used against similar category income.  Thus for capital gain/loss , one first reconciles  short-term losses with short-term then long term against long-term  and finally  against other passive losses/gains /gain etc

[cok]

Short term loss (stock) in 2019 that is like to offset short term gain (stock) or long term gain (also stock)

[pk]

TurboTax will that for you , as long as it has the federal carry-over worksheet from last year

[cok]

I’d like to carry back the loss from 2019 into 2018

[pk]

you would have to amend 2018 return -- you have to use all you can in 2019 and then the remainder can be carried backward / forward. Tell TurboTax that you want to carry back ---- I do not know if this possible  using the online version ( not familiar -- I will flag it for another SU to help ).  I know using the desk top version  and some familiarity with forms mode  it is reasonable to do.

[cok]

Ok!

[rjs]

Capital losses (short-term or long-term) cannot be carried back to an earlier year. You report the loss in the year that you sold the stock. If the loss cannot all be used that year, it will be carried forward to subsequent years. Up to $3,000 of the loss will be used each year to offset other income (besides capital gains).

This has nothing to do with whether you use TurboTax Online or the CD/Download ("desktop") TurboTax software. How capital losses are applied is determined by the tax law.