I am filing amended tax returns for year 2015 because I did not adjust the cost basis for ESPP stock sale. If this was the only change, which forms do I need to attach?

[punekr]

I am filing amended tax returns for year 2015 because I did not adjust the cost basis for ESPP stock sale.

I learned how to correctly enter all the information for cost basis calculation in Turbotax while filing 2016 tax return. So I used Turbotax 2015 to amend my 2015 return.

This is the only change in my amended tax return. While mailing, which forms do I need to attached in addition to all the standard forms printed from Turbotax ?

[TomYoung]

There's no "in addition to all the standard forms printed from TurboTax"; you mail in all the Forms and Schedules that changed from your original "as filed" income tax return along with the Form 1040X.  (It would be nice if TurboTax, understanding that you're amending, would print out a nice packet consisting of Form 1040X and every Form and Worksheet that's different than your "as filed" income tax return, but it doesn't.  You'll need to select what Forms and Schedules to print.)

Off hand it seems like your Form(s) 8949 where the sales were originally reported would change along with Schedule D.

Tom Young