For RSU and ESPP cost basis information differs between 1099-B and supplemental inform form

[jeff_qwb]

  I want to enter the cost basis (line 1e) for an E-Trade 1099-B.  there was also a supplemental information form document along with the 1099-B.  But cost basis information differs between 1099-B and supplemental information form. when I am claiming RSU and ESPP cases,  which document I should use?

My best guess is I should use an adjusted cost basis from the supplemental information form instead of 1099-B for both RSU and ESPP cases, want to confirm with tax experts here.

[GeorgeM777 · Accepted solution]

Yes, use the Supplemental Information rather than the original 1099-B you received, at least for the RSU and ESPP transactions that have been updated through the Supplemental Information.  To the extent the Supplemental Information does not contain or update other information on your 1099-B, then for those transactions continue to refer to your original 1099-B.

Generally, the Supplemental Information form will contain information indicating why you are receiving such document, and how it should be used in connection with preparing your tax return.  If there is any information in your Supplemental Information that seems to suggest that it should not be used as a supplement to your 1099-B, follow-up with additional information so that we might better assist you.  However, Supplemental Information documents are meant to update information on your 1099-B that was not available to the brokerage firm at the time the original 1099-B was prepared and thus, it was necessary to send the Supplemental Information document.  Therefore, use the Supplemental Information.  

@jeff_qwb