Do I need to amend my 2016 tax return if I received a 1099b reporting a capital loss after I filed last year or can I start reporting the loss this year?

[tmk41999]

I received a 1099b last year reporting a long term capital loss of $21,000 for disposed stock.  I had already filed my 2016 taxes when I received this.  Do I need to go back and amend my 2016 tax return before I can report a long term capital loss for 2017?  Can I report a loss of $3000 per year for 7 years?

[TomYoung · Accepted solution]

You need to amend your 2016 income tax return, that's the only way you can legitimately claim the capital loss.  You should amend your 2016 income tax return before you file your 2017 income tax return.  That way you'll know, accurately, what you loss carryover to 2017 is and enter that loss carryover in your 2017 income tax return.

How to amend: https://ttlc.intuit.com/questions/1894381-how-to-amend-change-or-correct-a-return-you-already-filed

Tom Young