If I did not report my short term capital loss in the previous year's tax return, can I report it this year?

[zuat34]

I had a $1,200 loss on my stock sales in 2019, however, I did not know that I should have reported it. Since I used free-version of Turbo Tax it was not even an option. This year I made another $2,000 loss in the stock market. Can I report the last year's loss together with this year's loss?

[ColeenD3]

No. Every tax year is separate. You will have to amend 2019 and you will have to upgrade to Premier to take the loss.

Amend your 2019 return if you need to change or correct something after you already filed it.

Keep in mind: You have 3 years from the date you filed your 2019 return (or 2 years after you paid the tax due, whichever is later) to file an amended return.

• How do I amend my 2019 TurboTax Online return?
• How do I amend my 2019 return in the TurboTax CD/Download software?

[Hal_Al]

Maybe, probably not.

As the other answer indicated it should have been reported on your 2019 tax return. If it will  not change your bottom line  (what you owed or got back), you do not need to amend. But you must account for how it would have been used, on your 2019 return,  in determining how much can be carried forward. 

Since the amount was less than $3000, it's all but certain that all of it would have been used up in 2019 and none can be used (carried forward to) this year.  The only way to be absolutely sure is to prepare a revised 2019 return. 

That said, here's a simple answer: if line 11b of  your 2019 return is $1200 or more, none of it would have carried forward to 2020..